Question 1archived
Select the number-pair in which the two numbers are related in the same way as are the two numbers of the following number-pair.
24 : 56
- A
12 : 36
- B
18 : 48
- C
15 : 40
- D
9 : 21
Show answer
D. 9 : 21The question asks us to find a number pair that shares the same relationship as the given pair, 24 : 56.
Understanding the Relationship in the Given Number Pair (24 : 56)
Let's analyze the relationship between 24 and 56. We can look for patterns like addition, subtraction, multiplication, division, or ratios. A common approach in such analogy problems is to examine the ratio between the two numbers.
The ratio of 24 to 56 can be written as $\frac{24}{56}$. We can simplify this fraction by finding the greatest common divisor (GCD) of 24 and 56. Both numbers are divisible by 8.
$\frac{24}{56} = \frac{24 \div 8}{56 \div 8} = \frac{3}{7}$
So, the relationship between 24 and 56 is a ratio of 3:7. This means the second number is $\frac{7}{3}$ times the first number ($24 \times \frac{7}{3} = 8 \times 7 = 56$).
Now, we need to examine the given options and find the pair that has the same 3:7 ratio (or where the second number is $\frac{7}{3}$ times the first number).
Analyzing the Options
Let's check each option to see if the ratio of the first number to the second number is 3:7.
Option 1: 12 : 36
The ratio is $\frac{12}{36}$.
Simplifying: $\frac{12}{36} = \frac{12 \div 12}{36 \div 12} = \frac{1}{3}$.
This ratio (1:3) is not the same as 3:7.
Option 2: 18 : 48
The ratio is $\frac{18}{48}$.
Simplifying: $\frac{18}{48} = \frac{18 \div 6}{48 \div 6} = \frac{3}{8}$.
This ratio (3:8) is not the same as 3:7.
Option 3: 15 : 40
The ratio is $\frac{15}{40}$.
Simplifying: $\frac{15}{40} = \frac{15 \div 5}{40 \div 5} = \frac{3}{8}$.
This ratio (3:8) is not the same as 3:7.
Option 4: 9 : 21
The ratio is $\frac{9}{21}$.
Simplifying: $\frac{9}{21} = \frac{9 \div 3}{21 \div 3} = \frac{3}{7}$.
This ratio (3:7) is the same as the ratio of 24 : 56.
Conclusion
Option 4, the pair 9 : 21, shows the same ratio of 3:7 as the given pair 24 : 56. Therefore, this is the correct number pair based on the shared relationship.
Number Pair
Ratio (First:Second)
Simplified Ratio
Matches 24:56 Ratio (3:7)?
24 : 56
24/56
3/7
Given Pair
12 : 36
12/36
1/3
No
18 : 48
18/48
3/8
No
15 : 40
15/40
3/8
No
9 : 21
9/21
3/7
Yes
Revision Table: Key Concepts in Number Analogies
Concept
Description
How it Applies Here
Number Analogy
Finding a relationship between numbers in a given pair and applying it to find a similar pair.
The relationship between 24 and 56 needs to be identified and matched.
Ratio
The quantitative relation between two amounts showing the number of times one value contains or is contained within the other. Expressed as a fraction or with a colon (:).
The ratio $\frac{24}{56}$ was found to be $\frac{3}{7}$, which is the core relationship.
Simplifying Ratios
Dividing both numbers in a ratio by their greatest common divisor (GCD) to get the simplest form.
Used to reduce $\frac{24}{56}$ to $\frac{3}{7}$ and check other options easily.
Logical Reasoning
The process of using rationality and inference to solve problems.
Analyzing number patterns and relationships is a form of logical reasoning.
Additional Information: Solving Analogy Problems
Number analogy questions are common in logical reasoning and quantitative aptitude tests. To solve them effectively, consider the following common relationships:
Arithmetic Operations: Addition, subtraction, multiplication, division. (e.g., $a : a+k$ or $a : a \times k$)
Squares and Cubes: Relationship involving squares or cubes of the number or numbers near it. (e.g., $n : n^2$ or $n : n^3$)
Digit Operations: Sum of digits, product of digits, etc.
Prime Numbers, Composite Numbers: Relationships based on number properties.
Ratio and Proportion: As seen in this problem, the ratio between the numbers is constant.
Combinations of Operations: Sometimes the relationship involves multiple steps (e.g., multiply by a number and then add another number).
Always test multiple possibilities for the relationship in the given pair before checking the options. Start with simple relationships like ratio or basic arithmetic, and move to more complex ones if needed.
Paper & answer key PDF ↗ Question 2archived
If HEAD is coded as 37 and BANK is coded as 57, then how will KITE be coded as?
- A
69
- B
87
- C
76
- D
91
Show answer
D. 91Understanding Letter Coding Patterns
This question asks us to decode a pattern used to represent words with numbers. We are given two examples: HEAD is coded as 37, and BANK is coded as 57. We need to find the coding for KITE using the same pattern.
Let's analyze the given examples to identify the logic behind the coding.
Analyzing the Coding for HEAD
The word is HEAD. Let's consider the alphabetical position of each letter (A=1, B=2, C=3, ..., Z=26).
H is the 8th letter.
E is the 5th letter.
A is the 1st letter.
D is the 4th letter.
Let's try summing the alphabetical positions:
\(8 + 5 + 1 + 4 = 18\)
The coded value is 37. How can 18 be related to 37? We can observe that \(18 \times 2 = 36\), and \(36 + 1 = 37\). This suggests a pattern: (Sum of alphabetical positions) \(\times 2 + 1\).
Analyzing the Coding for BANK
Let's test this pattern with the second example, BANK. The alphabetical positions are:
B is the 2nd letter.
A is the 1st letter.
N is the 14th letter.
K is the 11th letter.
Summing the alphabetical positions:
\(2 + 1 + 14 + 11 = 28\)
Now, applying the hypothesized pattern: \((Sum) \times 2 + 1\)
\(28 \times 2 + 1 = 56 + 1 = 57\)
This matches the given code for BANK. So, the pattern is consistent for both examples.
Applying the Pattern to KITE
Now we apply the identified pattern to the word KITE.
First, find the alphabetical position of each letter:
K is the 11th letter.
I is the 9th letter.
T is the 20th letter.
E is the 5th letter.
Next, sum the alphabetical positions:
\(11 + 9 + 20 + 5 = 45\)
Finally, apply the pattern: \((Sum) \times 2 + 1\)
\(45 \times 2 + 1 = 90 + 1 = 91\)
Therefore, KITE will be coded as 91.
Summary of Coding Pattern
Word
Alphabetical Positions
Sum of Positions
Pattern: Sum \(\times 2 + 1\)
Coded Value
HEAD
H(8), E(5), A(1), D(4)
\(8+5+1+4 = 18\)
\(18 \times 2 + 1\)
37
BANK
B(2), A(1), N(14), K(11)
\(2+1+14+11 = 28\)
\(28 \times 2 + 1\)
57
KITE
K(11), I(9), T(20), E(5)
\(11+9+20+5 = 45\)
\(45 \times 2 + 1\)
91
The coding for KITE is 91.
Revision Table: Letter Coding Analysis
Key Concepts in Letter Coding
Concept
Description
Example Use
Alphabetical Position
Assigning a number to each letter based on its order (A=1, B=2, ...).
Used in the HEAD/BANK/KITE problem.
Reverse Alphabetical Position
Assigning a number in reverse order (Z=1, Y=2, ...).
Sometimes used in coding problems.
Sum of Positions
Adding the numerical values of the letters in a word.
Often the base for the coding pattern.
Mathematical Operations
Applying operations like multiplication, addition, subtraction, division to the sum or individual values.
The pattern here was \(\times 2 + 1\).
Additional Information: Solving Coding Decoding Questions
Solving coding-decoding questions requires observation and pattern recognition. Here are some strategies:
Write down the alphabetical positions (1-26) and reverse positions (26-1) for quick reference.
Check for simple patterns first: sum of positions, reverse sum, difference, etc.
Look for common mathematical operations applied to the sum or individual positions.
Consider patterns based on vowels and consonants.
If letters are coded as other letters, check shifts (e.g., A becomes C, B becomes D - a +2 shift).
Always test the hypothesized pattern with all given examples before applying it to the word you need to code.
Practice with different types of coding questions helps improve pattern recognition skills.
Paper & answer key PDF ↗ Question 3archived
Which number will replace the question mark (?) in the following series?
16, 24, 36, ?, 81
- A
52
- B
54
- C
61
- D
58
Show answer
B. 54Finding the Missing Number in a Series
Let's analyze the given number series: 16, 24, 36, ?, 81. We need to find the number that replaces the question mark.
To solve a number series problem, we look for a mathematical pattern between consecutive terms. Common patterns include addition, subtraction, multiplication, division, or a combination of these, sometimes involving squares, cubes, or other sequences.
Let's examine the relationship between the terms:
From 16 to 24: The difference is $24 - 16 = 8$. The ratio is $\frac{24}{16} = \frac{3}{2} = 1.5$.
From 24 to 36: The difference is $36 - 24 = 12$. The ratio is $\frac{36}{24} = \frac{3}{2} = 1.5$.
We can see a consistent ratio of 1.5 between consecutive terms. This suggests the pattern is multiplication by 1.5 (or $\frac{3}{2}$). Let's assume this pattern continues throughout the series.
Applying the Multiplicative Pattern to Find the Missing Term
Following the pattern, the next term after 36 should be obtained by multiplying 36 by 1.5.
Calculation:
Missing term = $36 \times 1.5$
Missing term = $36 \times \frac{3}{2}$
Missing term = $\frac{108}{2}$
Missing term = $54$
So, the number replacing the question mark is 54.
Verifying the Pattern with the Last Term
Let's check if applying the same pattern to 54 gives us the last term, 81.
Next term = $54 \times 1.5$
Next term = $54 \times \frac{3}{2}$
Next term = $\frac{162}{2}$
Next term = $81$
This matches the last term in the series. Therefore, the identified pattern is correct.
The completed series is 16, 24, 36, 54, 81.
Term
Calculation from previous term
16
Given
24
$16 \times 1.5$
36
$24 \times 1.5$
54
$36 \times 1.5$
81
$54 \times 1.5$
The number that replaces the question mark (?) in the given series is 54.
Revision Table: Number Series Concepts
Understanding different types of number series patterns is key to solving these problems.
Pattern Type
Description
Example
Arithmetic Series
Adding or subtracting a constant difference.
2, 5, 8, 11, ... (add 3)
Geometric Series
Multiplying or dividing by a constant ratio.
3, 6, 12, 24, ... (multiply by 2)
Difference Series
The differences between terms form a pattern (e.g., arithmetic, geometric).
1, 2, 4, 7, 11, ... (differences are 1, 2, 3, 4, ...)
Mixed Series
Combination of patterns or alternating patterns.
1, 5, 2, 6, 3, 7, ... (alternating add 4, subtract 3)
Fibonacci-like Series
Each term is the sum of the previous two terms (or similar rule).
1, 1, 2, 3, 5, 8, ...
Additional Information on Solving Number Series Problems
Here are some tips for tackling number series questions in competitive exams or tests:
Look for simple arithmetic progressions (constant difference).
Check for geometric progressions (constant ratio).
Analyze the differences between consecutive terms – they might form a simpler series.
Look for differences between the differences (second-order differences).
Consider squares, cubes, square roots, or cube roots of the term numbers or the terms themselves.
Check for alternating patterns.
Sometimes the pattern involves operations on the digits of the numbers.
Practice with various types of number series to recognize patterns quickly.
Don't spend too much time on one question; if a pattern isn't obvious, move on and come back if time permits.
Solving number series requires keen observation and practice to identify the underlying mathematical rule.
Paper & answer key PDF ↗ Question 4archived
Three of the following four numbers are alike in a certain way and one is different. Pick the number that is different from the rest.
- A
953
- B
312
- C
523
- D
734
Show answer
A. 953Finding the Different Number: Odd One Out Pattern
The question asks us to identify the number that is different from the others in a given set of four numbers. This type of problem requires finding a pattern or rule that applies to three of the numbers, but not to the fourth one. The numbers provided are 953, 312, 523, and 734.
To solve this odd one out problem, let's examine the digits of each number and look for a consistent relationship or property.
Number 1: 953
Number 2: 312
Number 3: 523
Number 4: 734
Let's try to find a mathematical relationship between the digits of each number. A common pattern involves arithmetic operations between the digits, such as addition, subtraction, multiplication, or division. Let's test if there's a relationship between the first two digits and the third digit.
Analyzing Digit Patterns in the Numbers
Let's consider the possibility that there's a relationship between the first digit, the second digit, and the third digit of each number.
For the number 312: The first digit is 3, the second digit is 1, and the third digit is 2. Let's see if a simple operation on the first two digits gives the third digit.
3 - 1 = 2
Here, the difference between the first and second digit equals the third digit.
For the number 523: The first digit is 5, the second digit is 2, and the third digit is 3. Let's check if the same pattern applies.
5 - 2 = 3
This number also follows the pattern: First digit - Second digit = Third digit.
For the number 734: The first digit is 7, the second digit is 3, and the third digit is 4. Let's check if the pattern holds.
7 - 3 = 4
This number also follows the pattern: First digit - Second digit = Third digit.
For the number 953: The first digit is 9, the second digit is 5, and the third digit is 3. Let's apply the same pattern.
9 - 5 = 4
In this case, the difference between the first and second digit is 4, which is not equal to the third digit (3). This number does not follow the pattern observed in the other three numbers.
The pattern found is that for three of the numbers (312, 523, and 734), the third digit is the result of subtracting the second digit from the first digit.
Number
First Digit
Second Digit
Third Digit
First Digit - Second Digit
Does it follow pattern?
953
9
5
3
9 - 5 = 4
No (4 ≠ 3)
312
3
1
2
3 - 1 = 2
Yes (2 = 2)
523
5
2
3
5 - 2 = 3
Yes (3 = 3)
734
7
3
4
7 - 3 = 4
Yes (4 = 4)
Based on this analysis, the number 953 is the one that does not fit the established pattern. Therefore, 953 is the number different from the rest.
Revision Table: Number Pattern Types
Pattern Type
Description
Example
Digit Operations
Relationship between digits using arithmetic (+, -, ×, ÷)
Sum of digits, product of digits, difference between digits. (e.g., A - B = C)
Properties of Numbers
Based on mathematical properties like prime/composite, even/odd, square/cube numbers.
One number is prime, others are composite. One number is even, others are odd.
Sequence Patterns
Numbers following a specific sequence rule (arithmetic progression, geometric progression, etc.)
Looking at how numbers might relate if arranged in a series (though not directly applicable here).
Visual/Structural
Patterns based on how digits look or their position.
Symmetry, repeating digits, palindromic numbers.
Additional Information: Analyzing Number Properties
When tackling odd-one-out questions with numbers, it's useful to consider various properties and relationships digits can have. Here are a few common approaches:
Digit Sums: Calculate the sum of the digits for each number. Sometimes one sum will be different (e.g., all others sum to an even number, one sums to an odd).
Digit Products: Calculate the product of the digits. Again, one might yield a different result based on some property.
Even/Odd Digits: Count how many even or odd digits are in each number. One number might have a different count (like in our example, 953 has all odd digits).
Ascending/Descending Order: Check if the digits within a number are in increasing or decreasing order.
Divisibility Rules: See if numbers are divisible by certain numbers (like 2, 3, 5, 10). One might not follow the same divisibility rule as the others.
Relationship between Place Values: Patterns might involve the relationship between the units digit, tens digit, hundreds digit, etc. (as seen in our solution where the hundreds and tens digit relate to the units digit).
Systematically checking these common patterns can help you find the rule that makes one number different.
Paper & answer key PDF ↗ Question 5archived
Select the Venn diagram that best illustrates the relationship between the following classes.
Indians, Females, Voters
- A
Option A (shown in image)
- B
Option B (shown in image)
- C
Option C (shown in image)
- D
Option D (shown in image)
Show answer
C. Option C (shown in image)Females can be Indians as well as voters.
And some voters also can be Indians.
Hence, option 3 is the correct answer.
Paper & answer key PDF ↗ Question 6archived
Select the combination of letters that when sequentially placed in the gaps of the given letter series will complete the series.
ca_bab_ad_ab_ad_ab
- A
dcabc
- B
dcbcb
- C
bcdcb
- D
cdbcd
Show answer
B. dcbcbThe correct answer is dcbcb.
Combination Series: A mix of different rules might be applied, such as alternating between an alphabetic progression and a repeating unit, or combining letters and numbers. Reverse or Alternating Patterns: The pattern might go in reverse alphabetic order or alternate between forward and backward movement. Solving letter series problems often requires careful observation, identifying potential repeating units, looking at differences or relationships between consecutive letters or groups, and systematically testing hypotheses.
Paper & answer key PDF ↗ Question 7archived
Select the set in which the numbers are related in the same way as are the numbers of the following set.
(5, 24, 7)
- A
(9, 63, 14)
- B
(6, 75, 11)
- C
(10, 71, 13)
- D
(8, 80, 12)
Show answer
D. (8, 80, 12)Understanding the Number Relation in the Given Set (5, 24, 7)
The problem asks us to identify the relationship between the numbers in the set (5, 24, 7) and find another set from the options that follows the same relationship. Let's denote the numbers in a set as \(A\), \(B\), and \(C\), where \(A\) is the first number, \(B\) is the middle number, and \(C\) is the third number.
For the given set (5, 24, 7):
\(A = 5\)
\(B = 24\)
\(C = 7\)
We need to find a pattern or rule that connects these three numbers. Let's try various common relationships:
Sum/Difference: \(A+C = 5+7 = 12\). How is 24 related to 12? \(12 \times 2 = 24\). So, \(B = 2 \times (A+C)\) is a possible rule.
Product: \(A \times C = 5 \times 7 = 35\). How is 24 related to 35? \(35 - 11 = 24\). Could there be a rule like \(B = A \times C - 11\)?
Squares/Cubes: \(A^2 = 5^2 = 25\), \(C^2 = 7^2 = 49\). How are these related to 24? Notice that \(49 - 25 = 24\). This suggests the rule \(B = C^2 - A^2\).
Let's test the rule \(B = C^2 - A^2\) on the original set:
\(C^2 - A^2 = 7^2 - 5^2 = 49 - 25 = 24\)
This matches the middle number \(B=24\). This seems to be the correct relationship.
Let's test the rule \(B = 2 \times (A+C)\) again, just to be sure:
\(2 \times (A+C) = 2 \times (5+7) = 2 \times 12 = 24\)
This also works for the original set. We will test both rules on the options, but \(B=C^2-A^2\) is often a distinct type of pattern in such problems.
Applying the Relation to Options
Now, let's apply the rule \(B = C^2 - A^2\) to each of the given options to see which set follows the same pattern.
Analyzing Option 1: (9, 63, 14)
\(A = 9\), \(B = 63\), \(C = 14\)
Calculate \(C^2 - A^2\): \(14^2 - 9^2 = 196 - 81 = 115\)
Compare with \(B\): \(115 \neq 63\)
This set does not follow the rule.
Analyzing Option 2: (6, 75, 11)
\(A = 6\), \(B = 75\), \(C = 11\)
Calculate \(C^2 - A^2\): \(11^2 - 6^2 = 121 - 36 = 85\)
Compare with \(B\): \(85 \neq 75\)
This set does not follow the rule.
Analyzing Option 3: (10, 71, 13)
\(A = 10\), \(B = 71\), \(C = 13\)
Calculate \(C^2 - A^2\): \(13^2 - 10^2 = 169 - 100 = 69\)
Compare with \(B\): \(69 \neq 71\)
This set does not follow the rule.
Analyzing Option 4: (8, 80, 12)
\(A = 8\), \(B = 80\), \(C = 12\)
Calculate \(C^2 - A^2\): \(12^2 - 8^2 = 144 - 64 = 80\)
Compare with \(B\): \(80 = 80\)
This set follows the rule \(B = C^2 - A^2\).
Let's quickly check the rule \(B = 2 \times (A+C)\) for Option 4:
\(2 \times (A+C) = 2 \times (8+12) = 2 \times 20 = 40\)
Here, \(40 \neq 80\). This confirms that \(B = C^2 - A^2\) is the intended rule, as it is the only one that matches the original set and exactly one option.
Identifying the Matching Set
Based on our analysis, the set that follows the same relationship as (5, 24, 7) is (8, 80, 12), because for this set, the middle number is equal to the square of the third number minus the square of the first number.
Set
A
B
C
\(C^2 - A^2\) Calculation
Result (\(C^2 - A^2\))
Follows Rule \(B = C^2 - A^2\)?
(5, 24, 7)
5
24
7
\(7^2 - 5^2 = 49 - 25\)
24
Yes
(9, 63, 14)
9
63
14
\(14^2 - 9^2 = 196 - 81\)
115
No (\(115 \neq 63\))
(6, 75, 11)
6
75
11
\(11^2 - 6^2 = 121 - 36\)
85
No (\(85 \neq 75\))
(10, 71, 13)
10
71
13
\(13^2 - 10^2 = 169 - 100\)
69
No (\(69 \neq 71\))
(8, 80, 12)
8
80
12
\(12^2 - 8^2 = 144 - 64\)
80
Yes (\(80 = 80\))
Revision Table: Number Set Analysis
Reviewing the steps and the identified pattern:
The core task is to find a consistent mathematical relationship within the numbers of the initial set and check which option's numbers satisfy the same relationship.
Initial Set: (5, 24, 7)
Identify potential relationships: sum, difference, product, squares, cubes, combinations.
Testing \(C^2 - A^2 = B\): \(7^2 - 5^2 = 49 - 25 = 24\). This works.
Test other options using this rule.
Option 4: (8, 80, 12)
Test \(C^2 - A^2 = B\): \(12^2 - 8^2 = 144 - 64 = 80\). This also works.
Confirming that other options do not follow this specific rule solidifies the choice of Option 4.
Additional Information: Number Reasoning Concepts
Questions involving number sets and finding analogous relationships are common in logical and quantitative reasoning tests. They assess your ability to identify patterns and apply rules.
Common patterns found in such number sets include:
Arithmetic Operations: Relationships based on sum, difference, multiplication, division between the numbers, or derived values like sum of digits. (e.g., \(A+B=C\), \(A \times k = B\), \(A+C = k \times B\))
Square and Cube Relations: Relationships involving squares or cubes of the numbers. (e.g., \(A^2 = B\), \(A^2 + C^2 = B\), \(C^2 - A^2 = B\), as seen in this problem)
Combined Operations: More complex rules combining different operations. (e.g., \(A \times C - (A+C) = B\))
Digit Based Logic: Rules involving the digits of the numbers rather than the numbers themselves.
Solving these problems often involves a systematic approach of testing common patterns until one fits the given set and then verifying it across the options.
Paper & answer key PDF ↗ Question 8archived
Three of the following four letter-clusters are alike in a certain way and one is different. Pick the odd one out.
- A
MLKP
- B
XVWZ
- C
TSRN
- D
DCBZ
Show answer
B. XVWZThis question asks us to identify the letter cluster that is different from the other three based on a certain pattern or rule. We need to examine the arrangement and relationship between the letters in each given cluster.
Analyzing Letter Cluster Patterns
Let's look at the letters in each cluster and their positions in the English alphabet or their sequence.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Examining Each Letter Cluster
MLKP Letter Pattern
Let's examine the sequence in the cluster MLKP:
M is followed by L (which is the letter before M in the alphabet).
L is followed by K (which is the letter before L in the alphabet).
So, M, L, and K are three consecutive letters in reverse alphabetical order.
K is followed by P. The difference between K (11th letter) and P (16th letter) is $+5$.
The pattern for the first three letters is consecutive and in reverse alphabetical order (M $\to$ L $\to$ K).
XVWZ Letter Pattern
Let's examine the sequence in the cluster XVWZ:
X is followed by V. V is two letters before X in the alphabet.
V is followed by W. W is one letter after V in the alphabet.
So, X, V, and W are NOT consecutive letters in reverse alphabetical order (or any simple consecutive order like forward or reverse).
W is followed by Z. The difference between W (23rd letter) and Z (26th letter) is $+3$.
The pattern for the first three letters (X $\to$ V $\to$ W) does not show a simple consecutive sequence in reverse alphabetical order like MLK.
TSRN Letter Pattern
Let's examine the sequence in the cluster TSRN:
T is followed by S (which is the letter before T in the alphabet).
S is followed by R (which is the letter before S in the alphabet).
So, T, S, and R are three consecutive letters in reverse alphabetical order.
R is followed by N. The difference between R (18th letter) and N (14th letter) is $-4$.
The pattern for the first three letters is consecutive and in reverse alphabetical order (T $\to$ S $\to$ R).
DCBZ Letter Pattern
Let's examine the sequence in the cluster DCBZ:
D is followed by C (which is the letter before D in the alphabet).
C is followed by B (which is the letter before C in the alphabet).
So, D, C, and B are three consecutive letters in reverse alphabetical order.
B is followed by Z. Starting from B and moving backward, B $\to$ A $\to$ Z. This is a movement of two steps backward (or a difference of $-2$ considering wrapping around).
The pattern for the first three letters is consecutive and in reverse alphabetical order (D $\to$ C $\to$ B).
Identifying the Odd Letter Cluster Out
Based on the analysis:
In MLKP, the first three letters (MLK) are consecutive in reverse alphabetical order.
In XVWZ, the first three letters (XVW) are NOT consecutive in reverse alphabetical order.
In TSRN, the first three letters (TSR) are consecutive in reverse alphabetical order.
In DCBZ, the first three letters (DCB) are consecutive in reverse alphabetical order.
Therefore, the cluster XVWZ is different from the other three because its first three letters do not follow the pattern of being consecutive in reverse alphabetical order.
Revision Table: Letter Cluster Analysis Summary
Letter Cluster
First Three Letters
Pattern of First Three
Relationship of 3rd to 4th
Follows Consecutive Reverse Pattern?
MLKP
M, L, K
Consecutive, Reverse Alphabetical
K $\to$ P (+5)
Yes
XVWZ
X, V, W
Not Consecutive, Reverse Alphabetical
W $\to$ Z (+3)
No
TSRN
T, S, R
Consecutive, Reverse Alphabetical
R $\to$ N (-4)
Yes
DCBZ
D, C, B
Consecutive, Reverse Alphabetical
B $\to$ Z (-2, wrap)
Yes
The table clearly shows that MLKP, TSRN, and DCBZ share the pattern of having the first three letters as consecutive letters in reverse alphabetical order, while XVWZ does not.
Additional Information: Letter Series Reasoning
Letter series and letter cluster problems are common in logical reasoning and verbal ability tests. They often require identifying patterns based on:
Alphabetical position of letters (e.g., A=1, B=2, etc.).
Differences in alphabetical positions between letters.
Consecutive letters (forward or backward).
Skipping letters (e.g., A, C, E skipping one letter).
Vowels or consonants.
Symmetrical patterns.
Combination of patterns (e.g., position difference combined with vowel/consonant).
Solving these problems involves careful observation, breaking down the cluster or series into segments, and testing different possible rules or patterns.
Paper & answer key PDF ↗ Question 9archived
Select the set in which the numbers are related in the same way as are the numbers of the following set.
(17, 12, 7)
- A
(39, 28, 19)
- B
(15, 19, 23)
- C
(23, 32, 39)
- D
(42, 34, 27)
Show answer
B. (15, 19, 23)Analyzing the Relationship in the Given Set
The problem asks us to identify a set of numbers that shares the same relationship as the numbers in the set (17, 12, 7).
Let's examine the relationship between the numbers in the given set (17, 12, 7).
The difference between the first number (17) and the second number (12) is: $\text{Difference}_1 = 17 - 12 = 5$.
The difference between the second number (12) and the third number (7) is: $\text{Difference}_2 = 12 - 7 = 5$.
We observe that the difference between consecutive numbers is constant, which is 5. The numbers are decreasing, so the common difference is actually -5. This type of sequence, where the difference between consecutive terms is constant, is called an arithmetic progression.
Checking the Options for the Same Relationship
Now, we will check each given option to see if its numbers are related in the same way, meaning they form an arithmetic progression (have a constant difference between consecutive terms).
Option 1: (39, 28, 19)
Difference between 39 and 28: $39 - 28 = 11$.
Difference between 28 and 19: $28 - 19 = 9$.
The differences (11 and 9) are not constant. This set does not form an arithmetic progression.
Option 2: (15, 19, 23)
Difference between 19 and 15: $19 - 15 = 4$.
Difference between 23 and 19: $23 - 19 = 4$.
The differences (4 and 4) are constant. This set forms an arithmetic progression with a common difference of +4. This set shares the same underlying relationship type (arithmetic progression) as the original set, although the common difference is different in value and sign.
Option 3: (23, 32, 39)
Difference between 32 and 23: $32 - 23 = 9$.
Difference between 39 and 32: $39 - 32 = 7$.
The differences (9 and 7) are not constant. This set does not form an arithmetic progression.
Option 4: (42, 34, 27)
Difference between 42 and 34: $42 - 34 = 8$.
Difference between 34 and 27: $34 - 27 = 7$.
The differences (8 and 7) are not constant. This set does not form an arithmetic progression.
Conclusion
The given set (17, 12, 7) is an arithmetic progression with a constant difference of -5. Among the given options, only the set (15, 19, 23) is also an arithmetic progression, with a constant difference of +4. Therefore, the set (15, 19, 23) is related in the same way as the set (17, 12, 7) because both are arithmetic progressions.
Set
Difference 1st & 2nd
Difference 2nd & 3rd
Constant Difference?
Relationship
(17, 12, 7)
$17 - 12 = 5$
$12 - 7 = 5$
Yes (5)
Arithmetic Progression
(39, 28, 19)
$39 - 28 = 11$
$28 - 19 = 9$
No
Not Arithmetic Progression
(15, 19, 23)
$19 - 15 = 4$
$23 - 19 = 4$
Yes (4)
Arithmetic Progression
(23, 32, 39)
$32 - 23 = 9$
$39 - 32 = 7$
No
Not Arithmetic Progression
(42, 34, 27)
$42 - 34 = 8$
$34 - 27 = 7$
No
Not Arithmetic Progression
Revision Table: Key Concepts for Number Analogy
Concept
Description
How it Applies Here
Arithmetic Progression
A sequence where the difference between consecutive terms is constant. This constant is called the common difference.
The core relationship in the given set (17, 12, 7) is that it's an arithmetic progression. We looked for another set that also fits this definition.
Number Analogy
Identifying the relationship or rule governing a set of numbers and applying it to other sets to find a match.
We analysed the pattern (relationship) in (17, 12, 7) and checked which option set followed the same type of pattern.
Common Difference
The constant value added to or subtracted from one term to get the next term in an arithmetic progression.
Calculated the common difference for the original set (-5) and each option set to check for consistency within each set.
Additional Information: Types of Number Series Patterns
Number analogy questions often test your ability to recognise patterns in number series. Besides arithmetic progressions, here are other common types of patterns you might encounter:
Geometric Progression: Each term after the first is found by multiplying the previous one by a fixed, non-zero number called the common ratio. Example: (2, 4, 8, 16...) - common ratio is 2.
Square Numbers or Cube Numbers: The terms are the squares ($1^2, 2^2, 3^2, \dots$) or cubes ($1^3, 2^3, 3^3, \dots$) of consecutive integers. Example: (1, 4, 9, 16...) - squares of 1, 2, 3, 4.
Prime Numbers: The terms are prime numbers in sequence. Example: (2, 3, 5, 7, 11...).
Fibonacci Sequence: Each term is the sum of the two preceding ones. Example: (0, 1, 1, 2, 3, 5, 8...).
Combined Operations: The pattern might involve alternating addition/subtraction, or a combination of arithmetic and multiplication/division, or a pattern based on the term number (e.g., $n^2 + 1$).
For number analogy problems, always look for the simplest relationship first, like constant differences or ratios, before considering more complex patterns.
Paper & answer key PDF ↗ Question 10archived
In a family of seven persons, B is the brother of A and the son of C. D is the son-in-law of C, who has two grandchildren, E and F. A is the mother of F, who is the niece of G. E is the son of G. If C has two children, how is E related D?
- A
Son
- B
Cousin
- C
Nephew
- D
Brother-in-law
Show answer
C. NephewAnalyzing the Blood Relation Puzzle
Let's break down the given information about the family of seven persons to determine the relationship between E and D. We will build a family structure step-by-step based on the clues provided.
Step-by-Step Relationship Analysis
B is the brother of A and the son of C. This means C is the parent of B and A. B is male. A is female (as deduced later).
D is the son-in-law of C. A son-in-law is married to a daughter. Since C has children A and B, and B is male, A must be the daughter of C, and D is married to A.
C has two grandchildren, E and F. These grandchildren must be the children of A or B.
A is the mother of F. Since A is C's daughter, F is a grandchild of C, confirming clue 3.
F is the niece of G. F is the child of A. For F to be the niece of G, G must be a sibling of A.
E is the son of G. E is also a grandchild of C (from clue 3), and G is a sibling of A.
C has two children. We know C has children A and B. Since F is the niece of G and G is A's sibling, G must be either A or B. F is A's child, so F cannot be A's niece. Therefore, G must be B.
Building the Family Structure
Based on the analysis, we can construct the following family structure:
C is a parent.
A and B are the two children of C.
B is male (brother of A). A is female (mother of F, married to D).
D is married to A. D is C's son-in-law.
A is the mother of F. F is C's grandchild.
G is B (from deduction). E is the son of G, so E is the son of B. E is C's grandchild.
Let's visualize the structure:
C
— Parent of —
A and B
A
— Married to —
D
A
— Mother of —
F
B (G)
— Father of —
E
A and B
— Siblings
E and F
— Grandchildren of —
C
Determining the Relationship between E and D
We need to find out how E is related to D.
D is the husband of A.
A is the sister of B.
E is the son of B.
D is married to A, whose brother is B. E is the son of B. Therefore, E is the son of D's brother-in-law (B is A's brother and D's brother-in-law). The son of one's brother-in-law is one's nephew.
So, E is the nephew of D.
Revision Table: Key Relationships
Relation
Persons Involved
Parent-Child
C to A, C to B
Siblings
A and B
Spouse
A and D
Mother-Son/Daughter
A to F
Father-Son
B to E
Grandparent-Grandchild
C to E, C to F
Aunt/Uncle-Niece/Nephew
A to E (Aunt), B to F (Uncle), B to E (Father)
Additional Information: Understanding Blood Relations
Blood relation questions test your ability to trace relationships between members of a family using given information. Key terms and concepts to remember include:
Direct Relations: Father, Mother, Son, Daughter, Brother, Sister.
Indirect Relations: Grandfather, Grandmother, Uncle, Aunt, Nephew, Niece, Cousin, Son-in-law, Daughter-in-law, Brother-in-law, Sister-in-law, etc.
Building a family tree diagram is often the easiest way to solve complex blood relation problems. Represent males with one symbol (e.g., square) and females with another (e.g., circle). Use lines to connect spouses and siblings, and vertical lines for parent-child relationships.
Pay close attention to genders specified in the problem (e.g., brother, sister, son, daughter). If gender is not explicitly stated (e.g., 'child'), do not assume it unless implied by other relations (like son-in-law/daughter-in-law).
Paper & answer key PDF ↗ Question 11archived
A square paper is folded and cut as shown below. How will it appear when unfolded?

- A
Option A (shown in image)
- B
Option B (shown in image)
- C
Option C (shown in image)
- D
Option D (shown in image)
Show answer
B. Option B (shown in image)Hence, option 2 is the correct answer.
Paper & answer key PDF ↗ Question 12archived
Arrange the following words in a logical and meaningful order.
1. Child
2. Marriage
3. Infant
4. Employment
5. Education
- A
4, 1, 3, 5, 2
- B
3, 5, 2, 4, 1
- C
3, 1, 5, 4, 2
- D
5, 2, 4, 1, 3
Show answer
C. 3, 1, 5, 4, 2Determining the Logical Sequence of Life Events
The task is to arrange the given words – Child, Marriage, Infant, Employment, Education – in a logical and meaningful order. This involves understanding the typical progression of human life stages and common life events.
Step-by-Step Analysis of Word Order
We examine each word to establish its position in a life timeline:
Infant (3): This is the earliest stage, representing a baby from birth up to one year old. It marks the beginning of life.
Child (1): Following infancy, a child is a young human being below the age of puberty or below the legal age of majority. This stage naturally comes after being an infant.
Education (5): This process typically starts during childhood and is fundamental for development and future opportunities. It is a key activity associated with childhood and adolescence.
Employment (4): This involves engaging in work, usually for pay. People typically seek employment after completing their education or during their adult years.
Marriage (2): This is a formal union, often between a man and a woman, typically entered into in adulthood, usually after achieving some level of personal and financial stability through education and employment.
Establishing the Meaningful Progression
Based on the analysis of life stages, the most logical and meaningful order is:
Start with the earliest life stage: Infant (3).
Move to the next developmental stage: Child (1).
Incorporate a major activity during childhood/adolescence: Education (5).
Follow with the stage of seeking work: Employment (4).
Conclude with a significant adult life event: Marriage (2).
This creates the sequence: Infant, Child, Education, Employment, Marriage.
The Final Logical Order
The words arranged in a logical and meaningful order correspond to the sequence:
3. Infant
1. Child
5. Education
4. Employment
2. Marriage
Thus, the correct numerical sequence is 3, 1, 5, 4, 2.
Paper & answer key PDF ↗ Question 13archived
Select the figure that will come next in the following figure series.

- A
Option A (shown in image)
- B
Option B (shown in image)
- C
Option C (shown in image)
- D
Option D (shown in image)
Show answer
D. Option D (shown in image)Pattern followed is:
Whole figure is Rotated by 45° in anticlockwise direction after each step.
Symbols inside figure are interchanging positions after each step.
Hence, is the answer.
Paper & answer key PDF ↗ Question 14archived
Two statements are given, followed by three conclusions numbered I, II and III. Assuming the statements to be true even if they seem to be at variance with commonly known facts, decide which of the conclusions logically follow(s) from the statements.
Statements:
Some carpenters are technicians.
All technicians are mechanics.
Conclusions:
I. Some carpenters are mechanics.
II. Some mechanics are technicians.
III. All carpenters are mechanics.
- A
None of the conclusions follows
- B
Only conclusions I and II follow
- C
Only conclusion I follows
- D
Only conclusions II and III follow
Show answer
B. Only conclusions I and II followUnderstanding Syllogism Statements and Conclusions
This question asks us to analyze two given statements and determine which of the three listed conclusions logically follow from them. This is a classic logical reasoning problem type called syllogism. We must assume the statements are true, regardless of whether they align with real-world knowledge.
Analyzing the Syllogism Statements
Let's break down the statements provided:
Statement 1: Some carpenters are technicians.
Statement 2: All technicians are mechanics.
In terms of sets, Statement 1 indicates an overlap between the set of 'carpenters' and the set of 'technicians'. Statement 2 indicates that the entire set of 'technicians' is included within the set of 'mechanics'.
Evaluating the Syllogism Conclusions
Now, let's evaluate each conclusion based on the logical relationship established by the statements:
Conclusion I: Some carpenters are mechanics.
Let's trace the relationship:
We know from Statement 1 that there is a group of people who are both carpenters and technicians.
We know from Statement 2 that everyone who is a technician is also a mechanic.
Combining these, the group of people who are carpenters and technicians must also be mechanics (because they are technicians, and all technicians are mechanics). Therefore, there exists a group of people who are carpenters and mechanics. This conclusion logically follows from the statements.
Conclusion II: Some mechanics are technicians.
Let's look at Statement 2 again: "All technicians are mechanics".
This means the set of technicians is a subset of the set of mechanics.
If all members of set A are also members of set B, then it necessarily follows that some members of set B are members of set A (specifically, all the members of set A).
So, if all technicians are mechanics, then some mechanics must be technicians. This conclusion logically follows from the statements.
Conclusion III: All carpenters are mechanics.
Let's consider the statements:
Statement 1 tells us that only *some* carpenters are technicians. We don't know anything about the carpenters who are *not* technicians from this statement.
Statement 2 tells us all technicians are mechanics.
The statements only guarantee that the carpenters who are also technicians are mechanics. They do not provide any information about the carpenters who are not technicians. These other carpenters might or might not be mechanics. Therefore, we cannot conclude that *all* carpenters are mechanics based on these statements alone. This conclusion does not logically follow.
Determining Which Conclusions Follow
Based on our analysis:
Conclusion I (Some carpenters are mechanics) follows.
Conclusion II (Some mechanics are technicians) follows.
Conclusion III (All carpenters are mechanics) does not follow.
Therefore, only conclusions I and II logically follow from the given statements.
Revision Table: Syllogism Analysis
Statement/Conclusion
Relationship Described
Logical Follows?
Reasoning
Statement 1
Some A are B (Carpenters, Technicians)
N/A
Given premise
Statement 2
All B are C (Technicians, Mechanics)
N/A
Given premise
Conclusion I
Some A are C (Carpenters, Mechanics)
Yes
Transitivity: Some (A & B) & All (B & C) $\implies$ Some (A & C)
Conclusion II
Some C are B (Mechanics, Technicians)
Yes
Converse of "All B are C" $\implies$ Some C are B
Conclusion III
All A are C (Carpenters, Mechanics)
No
Statements don't cover carpenters who are not technicians.
Additional Information on Syllogisms and Logic
Syllogisms are a form of deductive reasoning where a conclusion is drawn from two or more premises. The statements are the premises, and the conclusions are the deductions made from them. The validity of a conclusion depends solely on whether it is logically necessitated by the premises, not on its real-world truth.
Key types of categorical propositions used in syllogisms include:
Universal Affirmative (A): All S are P (e.g., All technicians are mechanics).
Universal Negative (E): No S are P (e.g., No carpenters are mechanics).
Particular Affirmative (I): Some S are P (e.g., Some carpenters are technicians).
Particular Negative (O): Some S are not P (e.g., Some carpenters are not mechanics).
Understanding the relationships between these types of statements is crucial for solving syllogism problems accurately. Techniques like Venn diagrams or rules of inference can be used to verify the validity of conclusions.
Paper & answer key PDF ↗ Question 15archived
Which two signs should be interchanged in the following equation to make it correct?
24 - 12 ÷ 4 + 8 × 2 = 11
- A
+ and -
- B
+ and ×
- C
and ÷
- D
+ and ÷
Show answer
A. + and -Analyzing the Sign Interchange Problem
This question asks us to find which two mathematical signs, when swapped in the given equation, make the equation correct. The original equation provided is: $24 - 12 \div 4 + 8 \times 2 = 11$
Evaluating the Original Equation
First, let's calculate the value of the left side of the original equation using the standard order of operations (BODMAS/PEMDAS - Brackets, Orders, Division and Multiplication, Addition and Subtraction).
Division: $12 \div 4 = 3$
Multiplication: $8 \times 2 = 16$
Now substitute these values back into the equation: $24 - 3 + 16$
Perform addition and subtraction from left to right: $24 - 3 = 21$, then $21 + 16 = 37$.
So, the original equation evaluates to $37$ on the left side, which is not equal to $11$. The equation is incorrect.
Testing Sign Interchanges
We need to test each option by swapping the specified signs and recalculating the left side of the equation to see if it equals $11$.
Option 1: Interchange + and - signs
If we swap the '+' and '-' signs in the original equation $24 - 12 \div 4 + 8 \times 2$, the new expression becomes $24 + 12 \div 4 - 8 \times 2$.
Let's evaluate this new expression:
Division: $12 \div 4 = 3$
Multiplication: $8 \times 2 = 16$
Substitute back: $24 + 3 - 16$
Addition and Subtraction: $24 + 3 = 27$, then $27 - 16 = 11$.
In this case, the left side evaluates to $11$, which matches the right side of the original target equation ($11$). So, interchanging '+' and '-' makes the equation correct.
Option 2: Interchange + and × signs
If we swap the '+' and '$\times$' signs, the expression becomes $24 - 12 \div 4 \times 8 + 2$.
Let's evaluate:
Division: $12 \div 4 = 3$
Multiplication: $3 \times 8 = 24$
Substitute back: $24 - 24 + 2$
Subtraction and Addition: $24 - 24 = 0$, then $0 + 2 = 2$.
The left side evaluates to $2$, which is not $11$.
Option 3: Interchange - and ÷ signs
If we swap the '-' and '$\div$' signs, the expression becomes $24 \div 12 - 4 + 8 \times 2$.
Let's evaluate:
Division: $24 \div 12 = 2$
Multiplication: $8 \times 2 = 16$
Substitute back: $2 - 4 + 16$
Subtraction and Addition: $2 - 4 = -2$, then $-2 + 16 = 14$.
The left side evaluates to $14$, which is not $11$.
Option 4: Interchange + and ÷ signs
If we swap the '+' and '$\div$' signs, the expression becomes $24 - 12 + 4 \div 8 \times 2$.
Let's evaluate:
Division: $4 \div 8 = 0.5$ or $\frac{1}{2}$
Multiplication: $0.5 \times 2 = 1$ or $\frac{1}{2} \times 2 = 1$
Substitute back: $24 - 12 + 1$
Subtraction and Addition: $24 - 12 = 12$, then $12 + 1 = 13$.
The left side evaluates to $13$, which is not $11$.
Summary of Results
Let's summarize the results in a table:
Signs Interchanged
New Equation
Evaluated Result
Correct? (Result = 11)
None (Original)
$24 - 12 \div 4 + 8 \times 2$
$37$
No
+ and -
$24 + 12 \div 4 - 8 \times 2$
$11$
Yes
+ and $\times$
$24 - 12 \div 4 \times 8 + 2$
$2$
No
- and $\div$
$24 \div 12 - 4 + 8 \times 2$
$14$
No
+ and $\div$
$24 - 12 + 4 \div 8 \times 2$
$13$
No
The summary table clearly shows that interchanging the '+' and '-' signs makes the equation correct.
Conclusion
The two signs that should be interchanged in the equation $24 - 12 \div 4 + 8 \times 2 = 11$ to make it correct are '+' and '-'.
Revision Table: Key Concepts
Concept
Description
Importance in Solving
Order of Operations (BODMAS/PEMDAS)
Rules defining the sequence for evaluating mathematical expressions (Brackets, Orders/Exponents, Division/Multiplication, Addition/Subtraction).
Essential for correctly calculating the value of the original and modified equations. Operations must be performed in the correct order.
Sign Interchange
Swapping the positions of two different mathematical operators within an expression.
The core operation required by the question to test different possibilities for correcting the equation.
Equation Verification
Checking if the value of the left side of an equation equals the value of the right side.
The final step after each sign interchange to determine if the equation has become correct (LHS = RHS).
Additional Information: Solving Mathematical Operations Problems
Problems involving mathematical operations and sign interchanging are common in competitive exams. They test your understanding of basic arithmetic operations and the strict adherence to the order of operations.
Systematic Approach: Always test each option methodically. Do not try to guess the correct interchange.
Recalculate Carefully: After swapping signs, carefully write down the new expression and evaluate it step-by-step using BODMAS/PEMDAS. A single calculation error can lead to the wrong conclusion.
Time Management: While being careful, practice evaluating expressions quickly to save time during an exam.
Understand Operator Precedence: Remember that multiplication and division have higher precedence than addition and subtraction. If they appear together, solve from left to right. Similarly for addition and subtraction.
By following these steps and understanding the concepts, you can efficiently solve mathematical operations problems involving sign changes.
Paper & answer key PDF ↗ Question 16archived
The average of 9 numbers is 40. If the average of the first five numbers is 38 and that of the last five is 50, then what is the fifth number?
- A
78
- B
90
- C
80
- D
84
Show answer
C. 80Understanding the Average Concept
The average, also known as the mean, is a fundamental concept in statistics. It is calculated by summing up all the values in a set and then dividing the sum by the total count of values in the set. The formula for average is:
\( \text{Average} = \frac{\text{Sum of Values}}{\text{Number of Values}} \)
From this formula, we can also find the sum of values if we know the average and the number of values:
\( \text{Sum of Values} = \text{Average} \times \text{Number of Values} \)
Solving the Average Problem Step-by-Step
We are given information about the average of different sets of numbers and need to find a specific number (the fifth number) which is part of two overlapping sets. Let's break down the given information and use the sum formula.
Step 1: Calculate the Total Sum of 9 Numbers
We are told the average of 9 numbers is 40. Using the sum formula:
\( \text{Sum of 9 numbers} = \text{Average of 9 numbers} \times \text{Number of 9 numbers} \)
\( \text{Sum of 9 numbers} = 40 \times 9 = 360 \)
Let the 9 numbers be \( n_1, n_2, n_3, n_4, n_5, n_6, n_7, n_8, n_9 \). Their sum is \( n_1 + n_2 + \dots + n_9 = 360 \).
Step 2: Calculate the Sum of the First Five Numbers
The average of the first five numbers is given as 38. These numbers are \( n_1, n_2, n_3, n_4, n_5 \).
\( \text{Sum of first 5 numbers} = \text{Average of first 5 numbers} \times \text{Number of first 5 numbers} \)
\( \text{Sum of first 5 numbers} = 38 \times 5 = 190 \)
So, \( n_1 + n_2 + n_3 + n_4 + n_5 = 190 \).
Step 3: Calculate the Sum of the Last Five Numbers
The average of the last five numbers is given as 50. These numbers are \( n_5, n_6, n_7, n_8, n_9 \).
\( \text{Sum of last 5 numbers} = \text{Average of last 5 numbers} \times \text{Number of last 5 numbers} \)
\( \text{Sum of last 5 numbers} = 50 \times 5 = 250 \)
So, \( n_5 + n_6 + n_7 + n_8 + n_9 = 250 \).
Step 4: Finding the Fifth Number Using Overlapping Sums
Notice that the fifth number (\( n_5 \)) is included in both the sum of the first five numbers and the sum of the last five numbers.
Let's consider the sum of the first five numbers plus the sum of the last five numbers:
\( (\text{Sum of first 5}) + (\text{Sum of last 5}) = (n_1 + n_2 + n_3 + n_4 + n_5) + (n_5 + n_6 + n_7 + n_8 + n_9) \)
\( 190 + 250 = n_1 + n_2 + n_3 + n_4 + 2 \times n_5 + n_6 + n_7 + n_8 + n_9 \)
\( 440 = (n_1 + n_2 + n_3 + n_4 + n_5 + n_6 + n_7 + n_8 + n_9) + n_5 \)
We know that \( n_1 + n_2 + \dots + n_9 \) is the sum of all 9 numbers, which is 360 (from Step 1).
\( 440 = (\text{Sum of 9 numbers}) + n_5 \)
\( 440 = 360 + n_5 \)
Now, we can find the value of the fifth number (\( n_5 \)):
\( n_5 = 440 - 360 \)
\( n_5 = 80 \)
Therefore, the fifth number is 80.
Description
Calculation
Result
Total Sum of 9 numbers
\( 40 \times 9 \)
360
Sum of first 5 numbers
\( 38 \times 5 \)
190
Sum of last 5 numbers
\( 50 \times 5 \)
250
Sum of first 5 + Sum of last 5
\( 190 + 250 \)
440
Fifth Number
\( (\text{Sum of first 5} + \text{Sum of last 5}) - (\text{Total Sum of 9}) \)
\( 440 - 360 = 80 \)
Revision Table: Key Average Formulas
Concept
Formula
Explanation
Average (Mean)
\( \text{Average} = \frac{\text{Sum of Values}}{\text{Count of Values}} \)
The sum of all values divided by the number of values.
Sum of Values
\( \text{Sum} = \text{Average} \times \text{Count of Values} \)
Calculated by multiplying the average by the total count. Useful when the sum is needed.
Finding Overlapping Element
\( \text{Overlapping Element} = (\text{Sum of Set 1} + \text{Sum of Set 2}) - \text{Sum of Combined Non-Overlapping Set} \)
Used when an element is counted in two different sums covering a larger set.
Additional Information on Average Problems
Problems involving averages often test your ability to work with the relationship between average, sum, and count. Overlapping sets, as seen in this question, are a common variation. Here are some points to remember:
Understanding Sum: The sum is the total value of all items. If you know the average and how many items there are, you can always find the sum.
Handling Overlaps: When two groups that overlap (share one or more elements) have their averages or sums given, the sum of the two groups will count the overlapping elements more than once. Subtracting the total sum of the combined unique elements gives you the value(s) of the overlapping element(s).
Weighted Average: Another common type of average problem involves different groups with different averages and counts. The weighted average is the total sum of all values divided by the total count of all values across all groups.
Mastering these basic concepts helps solve a wide range of average-based quantitative aptitude questions. Always read the question carefully to identify which numbers or sums are given and what is being asked.
Paper & answer key PDF ↗ Question 17archived
Select the figure in which the given figure is embedded.

- A
Option A (shown in image)
- B
Option B (shown in image)
- C
Option C (shown in image)
- D
Option D (shown in image)
Show answer
A. Option A (shown in image)Hence, option 1 is the correct answer.
Paper & answer key PDF ↗ Question 18archived
How many triangles are there in the following figure?

- A
18
- B
24
- C
14
- D
22
Show answer
Question 19archived
Select the mirror image of the given figure when the mirror is placed to the right of the figure.

- A
Option A (shown in image)
- B
Option B (shown in image)
- C
Option C (shown in image)
- D
Option D (shown in image)
Show answer
A. Option A (shown in image)Hence, the correct answer is option 1.
Paper & answer key PDF ↗ Question 20archived
In a code language, PASTEUR is coded as TPRUASE. How would SEVENTY be coded in that language?
- A
NSYTEVN
- B
ENVETYS
- C
ESYTEVN
- D
ESYETNV
Show answer
C. ESYTEVNThis question involves a code language where words are coded based on a specific pattern. We are given the coding for the word PASTEUR and need to find the coding for the word SEVENTY using the same rule.
Understanding the Code Language Pattern
Let's analyze the given example: PASTEUR is coded as TPRUASE.
Both words have 7 letters. Let's assign positions to the letters in the original word PASTEUR:
\(P_1 A_2 S_3 T_4 E_5 U_6 R_7\)
Now, let's look at the positions of these letters in the coded word TPRUASE:
\(T_1 P_2 R_3 U_4 A_5 S_6 E_7\)
We need to figure out which original position corresponds to which coded position. Let's map the letter from its original position to its new position in the coded word:
The letter at original position 1 (P) is at coded position 2.
The letter at original position 2 (A) is at coded position 5.
The letter at original position 3 (S) is at coded position 6.
The letter at original position 4 (T) is at coded position 1.
The letter at original position 5 (E) is at coded position 7.
The letter at original position 6 (U) is at coded position 4.
The letter at original position 7 (R) is at coded position 3.
This means the coded word is formed by taking the letters from the original word based on a specific sequence of original positions. Let's list which original position's letter goes into each coded position:
Coded Position
Letter is from Original Position
Example (PASTEUR)
1
4
T
2
1
P
3
7
R
4
6
U
5
2
A
6
3
S
7
5
E
So, the order of original positions used to form the coded word is 4, 1, 7, 6, 2, 3, 5.
Applying the Pattern to Code SEVENTY
Now we apply the same positional rearrangement pattern to the word SEVENTY. First, assign positions to the letters in SEVENTY:
\(S_1 E_2 V_3 E_4 N_5 T_6 Y_7\)
Using the pattern (Original Positions: 4, 1, 7, 6, 2, 3, 5) to pick letters for the coded word:
Coded Position
Get Letter from Original Position
Letter from SEVENTY
1
4
E
2
1
S
3
7
Y
4
6
T
5
2
E
6
3
V
7
5
N
Reading the letters in order for the coded positions (1 through 7), we get E S Y T E V N.
Conclusion
Based on the coding pattern derived from PASTEUR being coded as TPRUASE, the word SEVENTY is coded as ESYTEVN.
Revision Table: Code Language Pattern
Original Word
Coded Word
Pattern (Original Pos > Coded Pos)
PASTEUR
TPRUASE
1>2, 2>5, 3>6, 4>1, 5>7, 6>4, 7>3
SEVENTY
ESYTEVN
1>2, 2>5, 3>6, 4>1, 5>7, 6>4, 7>3
Alternatively, looking at which Original Position's letter goes to which Coded Position:
Coded Position
Letter from Original Position
1
4
2
1
3
7
4
6
5
2
6
3
7
5
Additional Information on Coding and Decoding
Coding and decoding questions are common in logical reasoning sections of competitive exams. They test your ability to identify patterns and rules.
Letter Coding: Involves patterns related to the alphabetic positions of letters, movement of letters within a word (like in this question), or substituting letters with other letters based on a rule.
Number Coding: Involves assigning numerical values to letters or words.
Symbol Coding: Uses symbols to represent letters or words.
To solve such problems, always look for a consistent rule applied to the example provided. The rule can be:
Shifting letters by a fixed number of positions in the alphabet.
Reversing the word or parts of the word.
Rearranging the letters based on their original positions (as seen in this PASTEUR example).
Substituting letters with their opposite letters in the alphabet.
Combining different rules.
Careful observation and breaking down the example are key to cracking the code.
Paper & answer key PDF ↗ Question 21archived
Select the option that is related to the third letter-cluster in the same way as the second letter-cluster is related to the first letter-cluster.
DGIL : WTRO ∷ FHKM : ?
- A
USPN
- B
QPLJ
- C
WTSP
- D
TRON
Show answer
A. USPNUnderstanding Letter Analogies in Reasoning
Letter analogies questions test your ability to find the relationship between a pair of letters or letter clusters and apply that same relationship to another pair. In this specific analogy, we are given the pair DGIL : WTRO and asked to find the letter cluster that relates to FHKM in the same way.
Analyzing the Relationship: DGIL to WTRO
Let's examine the relationship between the letters in the first pair, DGIL and WTRO. We can look at their positions in the English alphabet (A=1, B=2, ..., Z=26).
D is the 4th letter. W is the 23rd letter.
G is the 7th letter. T is the 20th letter.
I is the 9th letter. R is the 18th letter.
L is the 12th letter. O is the 15th letter.
Let's look for a pattern in the positional values:
D (4) and W (23): $4 + 23 = 27$
G (7) and T (20): $7 + 20 = 27$
I (9) and R (18): $9 + 18 = 27$
L (12) and O (15): $12 + 15 = 27$
The pattern here is that each letter in the second cluster (WTRO) is the 'opposite' letter of the corresponding letter in the first cluster (DGIL). Opposite letters are pairs whose positional values sum up to 27. For example, A (1) and Z (26) are opposites because $1 + 26 = 27$.
Applying the Same Logic to FHKM
Now, we will apply this 'opposite letter' rule to the third letter cluster, FHKM.
Let's find the positional values of the letters in FHKM:
F is the 6th letter.
H is the 8th letter.
K is the 11th letter.
M is the 13th letter.
Now, let's find the letters whose positional values sum up to 27 with these values:
For F (6): The opposite letter's position is $27 - 6 = 21$. The 21st letter is U.
For H (8): The opposite letter's position is $27 - 8 = 19$. The 19th letter is S.
For K (11): The opposite letter's position is $27 - 11 = 16$. The 16th letter is P.
For M (13): The opposite letter's position is $27 - 13 = 14$. The 14th letter is N.
Combining these opposite letters, we get the cluster USPN.
First Cluster (DGIL)
Position
Relationship (Sum = 27)
Second Cluster (WTRO)
Position
D
4
$4 + 23 = 27$
W
23
G
7
$7 + 20 = 27$
T
20
I
9
$9 + 18 = 27$
R
18
L
12
$12 + 15 = 27$
O
15
Third Cluster (FHKM)
Position
Relationship (Sum = 27)
Fourth Cluster (?)
Position
F
6
$6 + 21 = 27$
U
21
H
8
$8 + 19 = 27$
S
19
K
11
$11 + 16 = 27$
P
16
M
13
$13 + 14 = 27$
N
14
Conclusion
Following the pattern observed in the first pair (DGIL : WTRO), the third letter cluster FHKM is related to USPN. We check the options provided.
Option 1: USPN
Option 2: QPLJ
Option 3: WTSP
Option 4: TRON
Our calculated letter cluster, USPN, matches Option 1.
Revision Table: Letter Analogy Review
Concept
Description
How it Applies Here
Letter Analogy
Finding the relationship between letter pairs.
Used to find the pattern DGIL > WTRO.
Letter Position
Numerical order of letters in the alphabet (A=1, B=2, ...).
Used to calculate sums and find relationships.
Opposite Letters
Pairs of letters whose positions sum to 27 (e.g., A & Z, B & Y).
The core relationship found in DGIL > WTRO.
Pattern Application
Applying the discovered relationship to a new case.
Applied the 'opposite letter' rule to FHKM.
Additional Information: Common Letter Reasoning Patterns
Letter analogy and reasoning problems often use various patterns. Here are some common types:
Positional Shift: Each letter is shifted forward or backward by a fixed number of positions (e.g., A+1 = B, A+3 = D).
Reverse Order: The letters in the cluster are reversed.
Alphabetical Series: Letters follow a specific sequence (e.g., skipping letters, increasing/decreasing gaps).
Vowel/Consonant Patterns: The pattern might involve vowels or consonants specifically.
Combination of Patterns: More complex analogies can combine shifts, reversals, or other rules.
Opposite Letters: As seen in this problem, using letter pairs that sum to 27.
Practicing with different types of letter patterns helps in quickly identifying the rule in analogy questions.
Paper & answer key PDF ↗ Question 22archived
Two different positions of the same dice are shown. Which number will be at the top if 5 is at the bottom?

- A
2
- B
3
- C
4
- D
6
Show answer
C. 4In 1 st cube we see that 1 and 3 are adjacent to 4.
In 2 nd cube we see that 2 and 6 are adjacent to 4.
Only remaining number 5 will be on opposite side of 4.
Hence, when 5 is at bottom 4 will be on top.
Paper & answer key PDF ↗ Question 23archived
‘Geology’ is related to ‘Rocks’ in the same way as ‘Cytology’ is related to ‘__________’.
- A
Life
- B
Plants
- C
Cells
- D
Organism
Show answer
C. CellsUnderstanding Science Analogies: Geology and Cytology
The question asks us to complete an analogy: ‘Geology’ is related to ‘Rocks’ in the same way as ‘Cytology’ is related to something else. Analogies test our understanding of the relationship between pairs of concepts.
Analyzing the First Part of the Analogy: Geology and Rocks
The first part of the analogy is the relationship between ‘Geology’ and ‘Rocks’. Geology is the scientific study of the Earth, its history, its composition, and its structure. A major part of geology involves studying rocks and minerals, how they form, and how they change over time. So, the relationship is that Geology is the study of Rocks (among other things related to the Earth).
Applying the Relationship to the Second Part: Cytology and the Unknown
We need to find what ‘Cytology’ is the study of, to match the relationship found in the first part of the analogy. Cytology is a specific branch of biology.
Defining Cytology
Cytology comes from the Greek words ‘cyto-’ meaning 'cell' and ‘-logia’ meaning 'study'. Therefore, Cytology is the scientific study of cells. This includes studying their structure, function, life cycle, and interactions with their environment.
Evaluating the Options
Now let's look at the given options to see which one fits the definition of what Cytology studies:
Option 1: Life - The study of life in general is called Biology. While cells are fundamental units of life, Cytology is not the study of all life.
Option 2: Plants - The study of plants is called Botany. Cells are parts of plants, but Cytology is not limited to just plant cells, and its scope is the cell itself, not the whole plant.
Option 3: Cells - As defined, Cytology is explicitly the scientific study of cells. This matches the required relationship.
Option 4: Organism - The study of organisms (whole living beings) falls under various branches of biology, such as organismal biology or zoology/botany depending on the type of organism. Cytology focuses on the cellular level, not the entire organism.
Identifying the Correct Relationship
The relationship in the first part is: [Field of Study] is the study of [Object of Study] (or is closely related to studying it). Applying this to the second part, Cytology is the study of Cells. Therefore, the analogy is correctly completed by ‘Cells’.
Field of Study
Primary Object of Study (in this context)
Geology
Rocks
Cytology
Cells
Thus, ‘Geology’ is related to ‘Rocks’ in the same way as ‘Cytology’ is related to ‘Cells’.
Revision Table: Key Terms and Definitions
Term
Definition / Relation
Geology
Scientific study of the Earth, including rocks.
Rocks
Solid mineral material forming part of the surface of the Earth; studied in Geology.
Cytology
Scientific study of cells.
Cells
The basic structural, functional, and biological unit of all known organisms; studied in Cytology.
Additional Information: Branches of Science Study
Science is divided into many branches, each focusing on a specific area of study. Here are a few examples related to the options:
Biology: The study of life and living organisms.
Botany: The study of plants.
Zoology: The study of animals.
Microbiology: The study of microorganisms.
Ecology: The study of the relationships between living organisms and their environment.
Geology: The study of the Earth's physical structure and substance, its history, and the processes that act on it.
Cytology: The study of cells.
Understanding these basic relationships between fields of study and their subjects is crucial for tackling analogy questions like this one.
Paper & answer key PDF ↗ Question 24archived
Three of the following four words are alike in a certain way and one is different. Pick the odd word out.
- A
Hinder
- B
Arrest
- C
Impede
- D
Steal
Show answer
D. StealThis question asks us to identify the word that is different from the others in a given list of four words: Hinder, Arrest, Impede, and Steal. To find the odd word out, we need to understand the meaning of each word and see how they relate to each other.
Understanding the Meaning of Each Word
Hinder: To create difficulties for someone or something, preventing them from achieving something. It means to obstruct or delay progress.
Arrest: In the context of stopping or slowing something down, it means to stop the progress or movement of something. (It can also mean taking someone into custody, but the other words suggest the meaning related to stopping progress).
Impede: To delay or prevent someone or something by obstructing them; hinder. This word is very similar in meaning to hinder.
Steal: To take something from someone unlawfully or without permission.
Comparing the Meanings
Let's look at how the first three words, Hinder, Arrest, and Impede, are related:
Hinder, Arrest (in the sense of stopping progress), and Impede all describe actions that slow down, block, or stop movement, progress, or action.
They are synonyms or near-synonyms related to obstruction or prevention of movement/progress.
Now, let's look at the word Steal:
Steal describes the act of taking property illegally.
This action of taking something unlawfully is completely different in meaning from the actions of hindering, arresting (in the sense of stopping progress), or impeding, which are about obstructing or delaying.
Identifying the Odd Word Out
Based on the comparison of meanings:
Hinder, Arrest, and Impede share a common theme of obstruction, delay, or prevention of progress. Steal is about taking property illegally, which has no relation to the concept of obstruction or delay.
Therefore, the word that is different from the others is Steal.
Conclusion on the Odd Word
The words Hinder, Arrest, and Impede are related in meaning, all implying some form of obstruction or stopping of progress. The word Steal has a completely different meaning related to theft. Thus, Steal is the odd word out.
The final answer is Steal.
Revision Table: Understanding Word Meanings
Let's quickly review the core meanings:
Word
Core Meaning Related to Others
Different Meaning
Hinder
Obstruct, delay, prevent progress
-
Arrest
Stop progress
Take into custody
Impede
Obstruct, delay, prevent progress
-
Steal
-
Take unlawfully (Theft)
This table clearly shows that Hinder, Arrest (in one sense), and Impede fall into one category of meaning (obstruction/stopping), while Steal falls into a completely different category (theft).
Additional Information on Synonyms
Understanding synonyms can help identify relationships between words. Words like 'obstruct', 'block', 'delay', and 'prevent' are synonyms for Hinder, Arrest (in the stopping sense), and Impede. Words related to 'Steal' include 'rob', 'burglarize', 'pilfer', and 'swipe'. These groups of synonyms highlight the distinct difference in meaning between Steal and the other three words.
Paper & answer key PDF ↗ Question 25archived
In the following question, select the related word pair from the given alternatives.
Commodity Exchange : Commodity
- A
Treatment : Disease
- B
Correspondence : letter
- C
Debate : Discussion
- D
Marching : Traffic
Show answer
B. Correspondence : letterUnderstanding Analogies: Commodity Exchange and Commodity
The question asks us to find a word pair that shares a similar relationship to the given pair, "Commodity Exchange : Commodity". To solve this, we first need to understand the relationship between the words in the original pair.
A Commodity Exchange is a marketplace or organized system where people buy and sell commodities. A Commodity is the item or raw material that is traded on the Commodity Exchange. So, the relationship is that the first word is the place or system where the second word (the item) is traded or dealt with.
Analyzing the Options for Related Pairs
Let's examine each option to see which one exhibits a similar relationship:
Option 1: Treatment : Disease
Treatment is something applied to cure or manage a Disease. The relationship is action-to-condition. This is not similar to the venue/system-to-item relationship of Commodity Exchange : Commodity.
Option 2: Correspondence : letter
Correspondence is the act or system of communication by exchanging letters. A letter is the item that is exchanged or dealt with in Correspondence. This relationship, where the first word is the system/activity involving the second word (the item of focus), is very similar to Commodity Exchange : Commodity.
Option 3: Debate : Discussion
A Debate is a formal type of Discussion. The relationship here is specific type-to-general category. This is not similar to the venue/system-to-item relationship.
Option 4: Marching : Traffic
Marching is an activity, and Traffic is the movement of vehicles or people. Marching can contribute to Traffic congestion or be part of Traffic flow, but it's not the venue or system for Traffic in the same way a Commodity Exchange is for a Commodity.
Identifying the Correct Analogy
Comparing the relationships, Option 2, "Correspondence : letter", shows the closest analogy to "Commodity Exchange : Commodity". Correspondence is the system or activity involving letters, just as a Commodity Exchange is the system or place involving commodities.
Conclusion on Commodity Analogy
Based on the analysis of the relationship between Commodity Exchange and Commodity, and comparing it with the relationships in the given options, the pair "Correspondence : letter" best fits the analogy.
Revision Table: Understanding Analogies
Original Pair
Relationship
Commodity Exchange : Commodity
Venue/System : Item Traded
Additional Information on Word Analogies
Word analogies questions test your ability to understand the relationship between a given pair of words and identify another pair that shares the same relationship. Common types of relationships include:
Part : Whole (e.g., Finger : Hand)
Cause : Effect (e.g., Heat : Expansion)
Synonyms (e.g., Happy : Joyful)
Antonyms (e.g., Hot : Cold)
Worker : Tool (e.g., Carpenter : Hammer)
Action : Object (e.g., Read : Book)
Location : Item (e.g., Library : Book)
System/Activity : Item (e.g., Correspondence : Letter)
Solving analogies often requires careful consideration of the precise connection between the words in the original pair and then applying that exact connection to the options.
Paper & answer key PDF ↗ Question 26archived
Which of the following elements is a lanthanide?
- A
Cerium
- B
Francium
- C
Actinium
- D
Polonium
Show answer
A. CeriumUnderstanding Lanthanide Elements
The question asks us to identify which of the given elements is a lanthanide. Lanthanides are a group of fourteen elements with atomic numbers from 58 (Cerium) to 71 (Lutetium). They are located in the f-block of the periodic table and are often shown as a separate row below the main body of the table, along with the actinides.
Identifying Lanthanides in the Periodic Table
Lanthanides, also known as the lanthanoids, follow the element Lanthanum (\(\text{La}\), atomic number 57). While Lanthanum itself is sometimes included or excluded depending on the definition, the fourteen elements from Cerium (\(\text{Ce}\)) to Lutetium (\(\text{Lu}\)) are always considered lanthanides. They are part of Period 6.
Let's examine each option provided to determine if it belongs to the lanthanide series:
Cerium (\(\text{Ce}\)): Cerium has an atomic number of 58. Looking at the definition, lanthanides start at atomic number 58. Therefore, Cerium is the first element in the lanthanide series.
Francium (\(\text{Fr}\)): Francium has an atomic number of 87. It is an alkali metal located in Group 1 and Period 7 of the periodic table. It is not a lanthanide.
Actinium (\(\text{Ac}\)): Actinium has an atomic number of 89. It is the first element in the actinide series, which are located below the lanthanides in the f-block and are part of Period 7. It is not a lanthanide.
Polonium (\(\text{Po}\)): Polonium has an atomic number of 84. It is a metalloid or metal located in Group 16 (the chalcogens) and Period 6 of the periodic table. It is not a lanthanide.
Comparing the Options
Based on the properties and positions of these elements in the periodic table, we can classify them:
Element
Symbol
Atomic Number
Classification
Cerium
\(\text{Ce}\)
58
Lanthanide
Francium
\(\text{Fr}\)
87
Alkali Metal
Actinium
\(\text{Ac}\)
89
Actinide
Polonium
\(\text{Po}\)
84
Metalloid/Metal
From the table and analysis, it is clear that Cerium is the only element among the options that belongs to the lanthanide series.
Conclusion on Lanthanide Identification
The question asks which element is a lanthanide. By checking the periodic table and the definition of lanthanides (elements 58-71), we confirmed that Cerium (\(\text{Ce}\), atomic number 58) is indeed a lanthanide element. The other options, Francium, Actinium, and Polonium, belong to different groups or series in the periodic table.
Revision Table: Lanthanides and Related Elements
Series/Group
Elements
Typical Location
Key Characteristics
Lanthanides
Ce (58) - Lu (71)
f-block, Period 6 (Row below main table)
Similar chemical properties, often called rare earth elements
Actinides
Ac (89) - Lr (103)
f-block, Period 7 (Row below main table)
Many are radioactive, all are metallic
Alkali Metals
Li, Na, K, Rb, Cs, Fr
Group 1
Highly reactive metals, form +1 ions
Chalcogens
O, S, Se, Te, Po, Lv
Group 16
Varying properties (nonmetal to metal)
Additional Information: The f-Block Elements
The lanthanides and actinides together make up the f-block elements. These elements are characterized by the filling of the f-orbitals. Because the f-orbitals are deeply buried within the atom, the valence electrons (in the outermost shells) are relatively unaffected by changes in the f-subshell configuration. This explains why lanthanides tend to have very similar chemical properties.
Understanding the arrangement of the periodic table, including the specific locations of the lanthanides and actinides, is crucial for classifying elements. Remember that the lanthanide series is typically shown starting after Barium (\(\text{Ba}\), 56) and Lanthanum (\(\text{La}\), 57) in Period 6, covering elements 58 through 71. Similarly, the actinide series follows Radium (\(\text{Ra}\), 88) and Actinium (\(\text{Ac}\), 89) in Period 7, covering elements 90 through 103.
Knowing the atomic numbers associated with these series can help quickly identify whether an element is a lanthanide or actinide.
Paper & answer key PDF ↗ Question 27archived
Special Olympics held every _____ years, is a global movement of people creating a new world of inclusion, where every single person is accepted and welcomed, regardless of their ability or disability.
- A
three
- B
five
- C
four
- D
two
Show answer
D. twoUnderstanding Special Olympics Frequency
The Special Olympics is a global movement dedicated to empowering people with intellectual disabilities through the power of sport. It aims to create a world where every person is accepted and welcomed, regardless of their abilities or disabilities, fostering a new world of inclusion.
A key aspect of the Special Olympics program is the staging of major international sports competitions. These events bring together athletes from around the world to compete, demonstrate their skills, and share their joy.
The question asks about the frequency at which the Special Olympics are held. Based on the organization's structure for major world events:
Special Olympics World Summer Games and Special Olympics World Winter Games are the flagship events.
These two major world events alternate every two years.
This means there is a Special Olympics World Games (either Summer or Winter) held every two years.
Therefore, the Special Olympics holds a major global event every two years, alternating between the Summer and Winter World Games. This consistent schedule helps maintain momentum for the movement and provides regular opportunities for athletes to compete on a global stage, promoting inclusion and acceptance worldwide.
Revision Table: Special Olympics Key Facts
Aspect
Description/Detail
Mission
Empowering people with intellectual disabilities through sports. Creating a world of inclusion.
Focus Group
Individuals with intellectual disabilities.
Global Events Frequency
Major World Games (Summer/Winter) held every two years, alternating.
Goal
Promote acceptance, inclusion, and sports participation for people with intellectual disabilities.
Additional Information on Special Olympics and Inclusion
The Special Olympics movement was founded by Eunice Kennedy Shriver. The first international Special Olympics Games were held in Chicago, Illinois, in 1968. Beyond the global World Games, Special Olympics operates year-round sports training and athletic competitions at local, regional, and national levels in communities worldwide.
It is important to understand the distinction between Special Olympics and Paralympics:
Special Olympics: Focuses specifically on athletes with intellectual disabilities, providing sports training and competition. Emphasis is on participation and personal best, alongside competition.
Paralympics: Caters to athletes with a wide range of physical disabilities and some intellectual disabilities (in specific sports like athletics, swimming, and table tennis, based on classification). It is a high-performance sports event for elite athletes with disabilities, often linked with the Olympic Games.
Both movements are vital for promoting sports for people with disabilities but serve different athlete populations and performance levels. The Special Olympics, through its frequent events every two years (alternating disciplines), consistently champions the cause of inclusion and acceptance for individuals with intellectual disabilities.
Paper & answer key PDF ↗ Question 28archived
In March 2019, the Central Board of Secondary Education (CBSE) announced the introduction of skill subjects in the school curriculum for the academic session 2019-20. Which of the following is NOT one of them?
- A
Yoga
- B
Early Childhood Care Education (ECCE)
- C
Artificial Intelligence (AI)
- D
Spiritual Enhancement
Show answer
D. Spiritual EnhancementUnderstanding CBSE Skill Subjects for 2019-20
This question concerns the skill subjects introduced by the Central Board of Secondary Education (CBSE) for the academic session beginning in 2019-20. The CBSE aimed to incorporate practical, skill-based learning into its curriculum to better prepare students for future careers and real-world challenges. We need to determine which of the listed options was not among these newly introduced skill subjects.
Analysis of Introduced Skill Subjects
The CBSE announced the introduction of several skill subjects in March 2019. Let's review the given options:
Yoga: This subject focuses on promoting physical and mental well-being through yoga practices. Yoga was indeed included as one of the skill subjects offered by CBSE for the 2019-20 academic session.
Early Childhood Care Education (ECCE): ECCE is designed to equip students with the necessary knowledge and skills related to the care, development, and education of young children. This was also formally introduced by CBSE as a skill subject.
Artificial Intelligence (AI): Recognizing the increasing importance of technology, CBSE introduced Artificial Intelligence as a skill subject. It covers fundamental concepts and applications of AI, preparing students for a tech-driven future. This was a key addition to the curriculum.
Spiritual Enhancement: While holistic development is a goal in education, "Spiritual Enhancement" as a standalone, formally structured skill subject within the CBSE's vocational or skill-based curriculum framework for 2019-20 is not typically listed among the officially announced subjects. The focus of the skill subjects was generally on vocational training and practical competencies.
Identifying the Subject Not Included
The core aim of the CBSE's initiative was to introduce subjects that provide vocational skills and career-oriented knowledge. Based on the common understanding and official lists of subjects introduced during that period:
Yoga, ECCE, and AI were confirmed subjects aimed at providing practical skills.
"Spiritual Enhancement," while potentially part of a school's broader educational philosophy, was not designated as a specific skill subject under the new framework introduced by CBSE for the 2019-20 academic year.
Therefore, 'Spiritual Enhancement' is the option that does not align with the specific skill subjects introduced by CBSE during that time.
Paper & answer key PDF ↗ Question 29archived
________, activist-journalist from Karnataka, who was shot dead in September 2017, was posthumously conferred the Anna Politkovskaya Award 2017.
- A
Gauri Lankesh
- B
Sudip Dutta Bhaumik
- C
Naveen Gupta
- D
Sayed Mehdi
Show answer
A. Gauri LankeshIdentifying the Activist-Journalist
The question asks us to identify a specific activist-journalist from Karnataka who was tragically shot dead in September 2017 and later received a prestigious international award, the Anna Politkovskaya Award, posthumously in 2017. Let's analyze the information provided and match it with the options.
Analysing the Key Information
The key details given in the question are:
Profession: Activist-journalist
Region: Karnataka, India
Event: Shot dead
Date: September 2017
Award: Anna Politkovskaya Award
Award Year: 2017 (posthumously conferred)
We need to find which of the given options matches all these criteria.
Evaluating the Options
Let's look at the provided options:
Gauri Lankesh: Gauri Lankesh was a prominent Indian journalist and activist from Karnataka. She was the editor of the Gauri Lankesh Patrike, a Kannada weekly. Sadly, she was shot dead outside her home in Bangalore, Karnataka, on September 5, 2017. Later that year, in October 2017, she was posthumously awarded the Anna Politkovskaya Award by Reach All Women in War (RAW in War) for her fearless journalism and activism. This option strongly aligns with all the details provided in the question.
Sudip Dutta Bhaumik: Sudip Dutta Bhaumik was a journalist in Tripura, India. He was shot dead in November 2017. While a journalist tragically killed in 2017, he was from Tripura, not Karnataka, and the award mentioned is specifically linked to a journalist from Karnataka killed in September 2017.
Naveen Gupta: Naveen Gupta was a journalist who was shot dead in Kanpur, Uttar Pradesh, in November 2017. He was not from Karnataka.
Sayed Mehdi: Information about a prominent activist-journalist named Sayed Mehdi matching the specific details of being from Karnataka, shot dead in September 2017, and receiving the Anna Politkovskaya Award in 2017 is not widely known or does not fit the description of the journalist tragically killed in Karnataka in September 2017.
Conclusion
Based on the analysis, Gauri Lankesh perfectly matches all the criteria mentioned in the question: she was an activist-journalist from Karnataka, she was shot dead in September 2017, and she was posthumously conferred the Anna Politkovskaya Award in 2017.
Key Facts about Gauri Lankesh
Born: November 29, 1962
Died: September 5, 2017
Location of death: Bangalore, Karnataka
Profession: Journalist, Editor (Gauri Lankesh Patrike), Activist
Award Received: Anna Politkovskaya Award (2017, posthumously)
Criteria
Gauri Lankesh
Sudip Dutta Bhaumik
Naveen Gupta
Sayed Mehdi
Profession
Activist-Journalist
Journalist
Journalist
Not widely known to fit criteria
State
Karnataka
Tripura
Uttar Pradesh
Not widely known to fit criteria
Death Month/Year
September 2017
November 2017
November 2017
Not widely known to fit criteria
Award
Anna Politkovskaya Award 2017 (Posthumous)
Does not match
Does not match
Does not match
Revision Table: Remembering Journalists and Awards
It is important for competitive exams to be aware of significant events related to journalism, freedom of press, and notable awards.
Journalist
Country/Region
Year of Incident
Notable Award (if any)
Anna Politkovskaya
Russia
2006 (Murdered)
namesake of the award
Gauri Lankesh
Karnataka, India
2017 (Murdered)
Anna Politkovskaya Award 2017
Jamal Khashoggi
Saudi Arabia
2018 (Murdered)
Several posthumous awards
Additional Information: The Anna Politkovskaya Award
The Anna Politkovskaya Award is presented annually by Reach All Women in War (RAW in War) to a female human rights defender who has stood up for victims of conflict, continues Anna Politkovskaya's legacy of speaking truth to power, and has shown courage and dedication.
Anna Politkovskaya was a Russian journalist and human rights activist known for her opposition to the Chechen conflict and for criticism of the Russian government. She was murdered in 2006.
Gauri Lankesh received this award for her brave work in India, championing freedom of the press and secular values, often in the face of threats.
Paper & answer key PDF ↗ Question 30archived
______ Strait separates the islands of Java (east) and Sumatra.
- A
Yucatan
- B
Sunda
- C
Cook
- D
Malacca
Show answer
B. SundaIdentifying the Strait Between Java and Sumatra
The question asks to identify the strait that separates the Indonesian islands of Java (specifically its eastern part) and Sumatra. This is a fundamental concept in geography, specifically concerning the major bodies of water and landforms.
Let's examine the options provided to determine which strait fits this description.
Understanding Straits
A strait is a narrow natural passageway of water that connects two larger bodies of water, and often separates two landmasses.
Analyzing the Options
Yucatan Strait: This strait is located between the Yucatan Peninsula of Mexico and the island of Cuba. It connects the Caribbean Sea to the Gulf of Mexico. Therefore, it does not separate Java and Sumatra.
Sunda Strait: This strait is situated between the islands of Java and Sumatra in Indonesia. It connects the Java Sea to the Indian Ocean. This location matches the description in the question.
Cook Strait: This strait separates the North Island and the South Island of New Zealand. It connects the Tasman Sea to the Pacific Ocean. It is not located near Indonesia and does not separate Java and Sumatra.
Malacca Strait: This is a busy shipping lane located between the Malay Peninsula (mainland Southeast Asia) and the island of Sumatra. While it borders Sumatra, it separates Sumatra from the Malay Peninsula, not from Java.
Based on the geographical locations, the Sunda Strait is the body of water that separates the islands of Java and Sumatra.
Major Straits and Separated Landmasses
Strait Name
Separates
Connects
Yucatan Strait
Yucatan Peninsula (Mexico) and Cuba
Caribbean Sea and Gulf of Mexico
Sunda Strait
Java (Indonesia) and Sumatra (Indonesia)
Java Sea and Indian Ocean
Cook Strait
North Island (New Zealand) and South Island (New Zealand)
Tasman Sea and Pacific Ocean
Malacca Strait
Malay Peninsula and Sumatra (Indonesia)
Andaman Sea and South China Sea
Therefore, the strait that separates the islands of Java and Sumatra is the Sunda Strait.
Revision Table: Straits and Their Locations
Strait
Key Islands/Landmasses Separated
Sunda Strait
Java and Sumatra
Malacca Strait
Sumatra and Malay Peninsula
Yucatan Strait
Mexico and Cuba
Cook Strait
North Island (NZ) and South Island (NZ)
Additional Information: Importance of Sunda Strait
The Sunda Strait is a significant waterway, though less famous than the nearby Strait of Malacca. It provides an alternative route for ships navigating between the Indian Ocean and the Pacific Ocean (specifically the Java Sea). It is also geologically active, located in a region prone to earthquakes and volcanic activity, most notably the Krakatoa volcano which is located within the strait itself.
Paper & answer key PDF ↗ Question 31archived
The Global Business Summit, launched on 15 January 2015, is a flagship initiative of the _____ Group.
- A
Economist
- B
Bhaskar
- C
Times
- D
Dutch
Show answer
C. TimesUnderstanding the Global Business Summit Initiative
The question asks about the organization behind the Global Business Summit, specifically mentioning its launch date of January 15, 2015. The Global Business Summit is known as a major platform that brings together global leaders, policymakers, academics, and corporate heads to discuss pressing economic and business issues.
Based on information about the event, the Global Business Summit is a significant initiative spearheaded by a prominent media conglomerate in India.
Let's consider the options provided:
Economist: The Economist Group is a well-known international media organization, but its flagship business events typically have different names.
Bhaskar: Dainik Bhaskar Group is a large Indian media group, primarily focused on Hindi newspapers. While they conduct events, the Global Business Summit is not typically associated with them.
Times: The Times Group (Bennett, Coleman & Co. Ltd.) is one of India's largest media conglomerates, publishing The Times of India newspaper, among other ventures. They are known for organizing large-scale events, including business summits.
Dutch: 'Dutch' refers to something related to the Netherlands and is not the name of a specific media or business group known for launching this particular summit.
Researching the origins of the Global Business Summit launched on January 15, 2015, confirms that it is indeed a flagship event organized by the Times Group.
Therefore, the Global Business Summit is a flagship initiative of the Times Group.
Revision Table: Key Details about the Global Business Summit
Feature
Detail
Event Name
Global Business Summit
Launch Date
January 15, 2015
Organizing Group
Times Group (Bennett, Coleman & Co. Ltd.)
Purpose
Platform for global leaders, policymakers, and businesses to discuss economic issues.
Additional Information on Business Summits
Business summits like the Global Business Summit play a crucial role in the global economy by:
Providing a platform for networking and collaboration among business leaders.
Facilitating discussions on current economic trends, challenges, and opportunities.
Influencing policy decisions by bringing together government officials and industry experts.
Showcasing investment opportunities in different regions or sectors.
Promoting international trade and business relations.
Different media groups and organizations worldwide host similar summits focusing on various aspects of business, economy, and technology.
Paper & answer key PDF ↗ Question 32archived
______ pass connects Uttarakhand and Tibet and is situated in the north of Gangotri.
- A
Shipki La
- B
Muling La
- C
Zoji La
- D
Bara Lacha La
Show answer
B. Muling LaUnderstanding Mountain Passes Connecting Uttarakhand and Tibet
The question asks us to identify a specific mountain pass that serves as a connection between Uttarakhand in India and Tibet (China) and is located geographically to the north of Gangotri.
Let's examine the given options and their locations:
Analyzing the Mountain Pass Options
Shipki La: This pass connects Himachal Pradesh (India) with Tibet. It is located in the Kinnaur district of Himachal Pradesh. Therefore, it does not connect Uttarakhand and Tibet.
Muling La: This pass is indeed situated in Uttarakhand and provides a route to Tibet. It is located in the northern part of Uttarakhand, specifically north of Gangotri. This location fits the description given in the question.
Zoji La: This pass is located in the Union Territory of Ladakh (historically Jammu and Kashmir). It connects Srinagar (Jammu and Kashmir) with Kargil and Leh (Ladakh). It does not connect Uttarakhand with Tibet.
Bara Lacha La: This pass is located in Himachal Pradesh and connects it with Ladakh. It is a high mountain pass in the Zanskar range, part of the Manali-Leh Highway. It does not connect Uttarakhand with Tibet.
Based on the analysis of each option, only Muling La fits the criteria of connecting Uttarakhand and Tibet and being located north of Gangotri.
Therefore, the correct mountain pass is Muling La.
Revision Table: Key Mountain Passes and Connections
Mountain Pass
Connects
Location Context
Muling La
Uttarakhand (India) and Tibet (China)
North of Gangotri, Uttarakhand
Shipki La
Himachal Pradesh (India) and Tibet (China)
Kinnaur district, Himachal Pradesh
Zoji La
Srinagar (J&K) and Kargil/Leh (Ladakh)
Union Territory of Ladakh
Bara Lacha La
Himachal Pradesh (India) and Ladakh (India)
Zanskar range, on Manali-Leh Highway
Additional Information on Himalayan Passes
Mountain passes are crucial geographical features in the Himalayan region, facilitating connectivity, trade, and historical movements across challenging terrain. These passes are often located at high altitudes and can be blocked by snow for significant parts of the year.
Passes connecting India and Tibet across the Himalayas are historically important trade routes.
Uttarakhand has several passes connecting it to Tibet, including Mana Pass, Niti Pass, Lipulekh Pass, besides Muling La.
Shipki La is one of the most important passes connecting India and Tibet via Himachal Pradesh.
Zoji La is vital for connectivity within India, linking the Kashmir Valley to Ladakh.
Bara Lacha La is a key high-altitude pass on a major road connecting Himachal Pradesh and Ladakh.
Paper & answer key PDF ↗ Question 33archived
Safdarjung's tomb, set in the middle of a garden, was built by Nawab Shuja-ud-Daulah in _______
- A
Uttarakhand
- B
Uttar Pradesh
- C
Delhi
- D
Bihar
Show answer
C. DelhiUnderstanding Safdarjung's Tomb Location
The question asks about the location of Safdarjung's tomb, which was built by Nawab Shuja-ud-Daulah and is situated in the middle of a garden.
Safdarjung's Tomb is a well-known historical monument in India.
Let's analyze the options provided:
Uttarakhand: This state is known for its Himalayan mountains and pilgrimage sites, but Safdarjung's tomb is not located there.
Uttar Pradesh: This state has many historical sites, including tombs and forts, particularly from the Mughal era (like those in Agra and Lucknow). Nawab Shuja-ud-Daulah was the Nawab of Awadh, a region now largely in Uttar Pradesh. However, Safdarjung's tomb is not in Uttar Pradesh.
Delhi: Delhi is home to numerous historical monuments from various periods, including many Mughal structures. Safdarjung's tomb is indeed located in Delhi.
Bihar: This state has its own rich history, particularly related to ancient India (like Magadha), but Safdarjung's tomb is not located there.
Historical records confirm that Safdarjung's tomb was built in Delhi. It was constructed by his son, Nawab Shuja-ud-Daulah, in 1754 after Safdarjung's death. The tomb is a prominent example of Late Mughal architecture and is set within a large garden complex, consistent with the description in the question.
Therefore, the correct location for Safdarjung's tomb is Delhi.
Safdarjung's Tomb Details and Context
Safdarjung was the Prime Minister (Wazir-ul-Mumalik) of the Mughal Emperor Ahmad Shah Bahadur. After his death, his son, Shuja-ud-Daulah, built this magnificent tomb for him.
Key features of Safdarjung's tomb:
It is the last monumental garden tomb of the Mughals in Delhi.
The tomb is built of marble and sandstone.
It follows the typical Mughal charbagh (four-garden) layout, with the main tomb structure in the center.
The architecture is influenced by Humayun's Tomb, an earlier and more grand Mughal tomb in Delhi.
Comparison of Locations and Tomb Presence
State/UT
Known for Safdarjung's Tomb?
Uttarakhand
No
Uttar Pradesh
No (though builder was Nawab of Awadh, largely in UP)
Delhi
Yes
Bihar
No
Conclusion on Safdarjung's Tomb Location
Based on historical evidence and the location of this famous monument, Safdarjung's tomb, built by Nawab Shuja-ud-Daulah, is located in Delhi.
Revision Table: Safdarjung's Tomb Facts
Aspect
Detail
Monument
Safdarjung's Tomb
Builder
Nawab Shuja-ud-Daulah (son of Safdarjung)
Subject of Tomb
Safdarjung (Mirza Muqim Abul Mansur Khan)
Year Built
1754
Architectural Style
Late Mughal
Setting
Charbagh (Four-part garden)
Location
Delhi, India
Additional Information: Safdarjung and Shuja-ud-Daulah
Safdarjung (Mirza Muqim Abul Mansur Khan) was an important figure in the decline of the Mughal Empire. He served as the Nawab of Awadh and later became the Wazir (Prime Minister) of the Mughal Emperor.
Nawab Shuja-ud-Daulah was Safdarjung's son and successor as the Nawab of Awadh. He built the tomb in memory of his father. Shuja-ud-Daulah is also known for his involvement in major historical events, including the Battle of Buxar.
The construction of Safdarjung's tomb in Delhi rather than Awadh (the primary domain of the Nawabs) reflects Safdarjung's position and influence within the Mughal court in Delhi.
Paper & answer key PDF ↗ Question 34archived
_________ has been called the "architect king" as during his reign, the world witnessed a unique development of arts and culture of the Mughal Empire.
- A
Shah Jahan
- B
Aurangzeb
- C
Jahangir
- D
Akbar
Show answer
A. Shah JahanUnderstanding the Mughal "Architect King"
The question asks to identify the Mughal emperor who was known as the "architect king" due to the significant development of arts and culture, particularly architecture, during his rule.
Let's analyze the reigns of the prominent Mughal emperors listed in the options to determine who fits this description best.
Analyzing the Mughal Emperors and Architecture
Akbar (reigned 1556–1605): Akbar was a great patron of art and architecture. His reign saw the construction of grand structures like Fatehpur Sikri, the Agra Fort, and Humayun's Tomb (built during his reign by his predecessor's wife). His architecture often blended Indian and Persian styles. While significant, he is more broadly known for his administrative reforms, religious tolerance, and expansion of the empire.
Jahangir (reigned 1605–1627): Jahangir's reign is particularly famous for its excellence in painting, rather than architecture. While architectural projects continued (like the tomb of Itmad-ud-Daulah, built by his wife Nur Jahan), the emphasis was arguably more on painting and gardens.
Shah Jahan (reigned 1628–1658): Shah Jahan's reign is widely regarded as the golden age of Mughal architecture. He commissioned numerous magnificent buildings, most famously the Taj Mahal in Agra, a mausoleum built for his wife Mumtaz Mahal. Other notable constructions include the Red Fort and Jama Masjid in Delhi, and sections of the Lahore Fort. His buildings are known for their elegance, use of white marble, intricate inlay work, and symmetrical designs. This extensive and unparalleled architectural output is why he is frequently referred to as the "architect king".
Aurangzeb (reigned 1658–1707): Aurangzeb was a less enthusiastic patron of arts and architecture compared to his predecessors. While some structures were built during his long reign (like the Badshahi Mosque in Lahore and the Bibi Ka Maqbara in Aurangabad), the scale and grandeur were generally reduced, and he did not share the same passion for commissioning elaborate buildings as Shah Jahan.
Identifying the "Architect King"
Based on the historical evidence and the sheer volume and magnificence of the architectural projects undertaken, Shah Jahan's reign stands out. His patronage led to the creation of some of the most iconic buildings of the Mughal era, earning him the title of the "architect king".
Therefore, the emperor who has been called the "architect king" is Shah Jahan.
Mughal Emperor
Reign Period
Key Architectural Contributions
Known For
Akbar
1556–1605
Fatehpur Sikri, Agra Fort, Humayun's Tomb (commenced)
Expansion, administration, syncretism, some architecture
Jahangir
1605–1627
Tomb of Itmad-ud-Daulah
Painting, gardens
Shah Jahan
1628–1658
Taj Mahal, Red Fort (Delhi), Jama Masjid (Delhi), Lahore Fort additions
Architecture (Golden Age), elegance, marble work
Aurangzeb
1658–1707
Badshahi Mosque, Bibi Ka Maqbara
Military campaigns, religious conservatism, less art patronage
Revision Table: Key Mughal Emperors and Contributions
Emperor
Period
Notable Fact/Contribution
Babur
1526-1530
Founder of the Mughal Empire
Humayun
1530-1540, 1555-1556
Empire consolidation, architectural interest (Humayun's Tomb began post-mortem)
Akbar
1556-1605
Expanded empire, Din-i Ilahi, Fatehpur Sikri
Jahangir
1605-1627
Patron of painting, gardens
Shah Jahan
1628-1658
Golden Age of Architecture, Taj Mahal, "Architect King"
Aurangzeb
1658-1707
Largest extent of empire, conservative policies
Additional Information on Mughal Architecture
Mughal architecture is a blend of Indian, Persian, and Islamic styles. Key features include:
Large domes
Arches
Minarets
Use of marble and red sandstone
Pietra dura (inlay work with precious and semi-precious stones)
Calligraphy
Extensive gardens (Charbagh style)
Shah Jahan's reign perfected many of these elements, particularly the use of white marble and pietra dura, achieving a level of refinement and grandeur that defined the peak of Mughal architectural style.
Paper & answer key PDF ↗ Question 35archived
It was under the reign of ______ that the Mughal Empire reached its peak in matter of area under the Mughal empire.
- A
Shah Jahan
- B
Akbar
- C
Jahangir
- D
Aurangzeb
Show answer
D. AurangzebUnderstanding the Territorial Peak of the Mughal Empire
The question asks about the reign during which the Mughal Empire reached its largest territorial extent in terms of area. To answer this, we need to consider the expansion efforts of the major Mughal emperors mentioned in the options.
The Mughal Empire was founded by Babur and expanded by his successors. Let's look at the reigns provided:
Akbar: Akbar is known for significantly expanding the empire, particularly in North India, Gujarat, Bengal, and parts of the Deccan. His reign laid the foundation for a vast empire.
Jahangir: Jahangir largely consolidated the territories inherited from Akbar, with some expansions in regions like Kangra and parts of the Deccan, but his reign didn't see the massive territorial growth characteristic of his father or son.
Shah Jahan: Shah Jahan continued the expansionist policy, particularly in the Deccan and towards the northwest frontier. He added territories like Daulatabad, Ahmadnagar, and parts of Bijapur to the empire.
Aurangzeb: Aurangzeb reigned for a long period and is known for his extensive military campaigns, particularly in the Deccan. He annexed the Sultanates of Bijapur and Golconda, pushing the southern boundary of the empire further than ever before. These annexations brought almost the entire Indian subcontinent under Mughal rule, except for the southernmost tips and some areas in the northeast.
Comparing the territorial extent under each ruler, historical records show that the empire reached its greatest physical size during Aurangzeb's reign due to his annexation of the Deccan sultanates.
Territorial Expansion Under Key Mughal Rulers
Let's summarise the approximate territorial extent during their reigns:
Ruler
Period of Reign
Key Areas Added
Approximate Empire Extent
Akbar
1556-1605
North India, Gujarat, Bengal, parts of Deccan
Vast parts of North and Central India, including parts of Deccan
Jahangir
1605-1627
Consolidated Akbar's gains, some Deccan territories
Maintained and slightly expanded Akbar's empire
Shah Jahan
1628-1658
More of Deccan, Kandahar (lost later), parts of Northwest
Further expansion in Deccan, large empire
Aurangzeb
1658-1707
Bijapur, Golconda, extensive parts of Deccan, parts of Northeast
Largest territorial extent, covered almost entire subcontinent
The significant campaigns in the Deccan, leading to the fall of Bijapur (1686) and Golconda (1687), were pivotal in making the Mughal Empire the largest it ever was in terms of area. Therefore, it was under the reign of Aurangzeb that the Mughal Empire reached its peak in matter of area.
Revision Table: Mughal Emperors and Empire Area
Mughal Emperor
Impact on Empire Area
Shah Jahan
Expanded further, especially in Deccan.
Akbar
Laid foundation for a vast empire, significant expansion.
Jahangir
Primarily consolidated, limited expansion.
Aurangzeb
Achieved maximum territorial extent through extensive Deccan campaigns.
Additional Information on Mughal Empire's Peak Area
The peak area of the Mughal Empire under Aurangzeb covered nearly the entire Indian subcontinent. This vast empire stretched from Kashmir in the north to Jinji in the south, and from Kabul in the west to Chittagong in the east. While Aurangzeb achieved the largest area, his long wars, especially in the Deccan, also put a significant strain on the empire's resources and administration. The sheer size of the empire also presented challenges in maintaining control over diverse regions.
Paper & answer key PDF ↗ Question 36archived
A situation where the expenditure of the government exceeds its revenue is called ______.
- A
Default Revenue
- B
Budget Deficit
- C
Default Financing
- D
Deficit Revenue
Show answer
B. Budget DeficitUnderstanding Government Finances: Expenditure vs. Revenue
The question asks for the specific term used when a government spends more money than it collects in revenue. This is a fundamental concept in public finance and economics.
What is a Budget Deficit?
A Budget Deficit occurs when the total expenditures (spending) of a government, organization, or even an individual exceed their total revenues (income) during a specific period, usually one fiscal year.
Think of it like your personal budget. If you spend $3,000 in a month but only earn $2,500, you have a deficit of $500 for that month. For a government, the principle is the same, but the numbers are much larger.
Formula for Budget Deficit
The concept can be represented with a simple formula:
\(\text{Budget Deficit} = \text{Total Government Expenditure} - \text{Total Government Revenue}\)
If the result is positive, it's a budget deficit. If it's negative, it's a budget surplus (revenue exceeds expenditure). If it's zero, it's a balanced budget.
Analyzing the Options
Let's look at the provided options in the context of the question:
Default Revenue: This is not a standard economic term related to government finances. 'Default' usually refers to failing to repay a debt.
Budget Deficit: As explained above, this term precisely describes the situation where government expenditure exceeds its revenue.
Default Financing: This term is not standard. 'Deficit financing' is a concept referring to how a government covers a budget deficit, for example, by borrowing money. It's about funding the gap, not the gap itself.
Deficit Revenue: This is not a standard economic term. Revenue is income; you don't have 'deficit revenue'.
Based on the standard definitions in economics and public finance, the situation where the government's expenditure exceeds its revenue is correctly identified as a Budget Deficit.
Why Budget Deficits Matter
Budget deficits are important because they often lead to the government needing to borrow money to cover the gap. This borrowing adds to the national debt. Persistent budget deficits can have various economic implications, such as potential pressure on interest rates, inflation, and future taxation.
Revision Table: Key Financial Terms
Term
Definition
Budget Deficit
Expenditure > Revenue
Budget Surplus
Revenue > Expenditure
Balanced Budget
Expenditure = Revenue
Government Expenditure
Money spent by the government (e.g., on services, infrastructure, salaries)
Government Revenue
Money collected by the government (e.g., from taxes, fees)
Additional Information on Government Finance
Government finances are managed through a budget, which is an annual plan detailing expected revenues and expenditures. The outcome of this budget process determines whether there is a budget deficit, surplus, or balance.
Governments can finance a budget deficit in several ways, most commonly by issuing bonds (borrowing from individuals, banks, or other countries). The impact of budget deficits and the resulting national debt is a frequent topic of economic and political discussion.
Understanding the difference between government expenditure and revenue and their relationship is key to understanding concepts like budget deficits and their economic consequences.
Paper & answer key PDF ↗ Question 37archived
Which of the following elements is an actinide?
- A
Lutetium
- B
Curium
- C
Ytterbium
- D
Erbium
Show answer
B. CuriumUnderstanding Actinide Elements
The question asks to identify an element that belongs to the actinide series of the periodic table. The periodic table is organized into groups and periods, and also includes special series like the lanthanides and actinides, typically placed below the main body.
What are Actinides?
The actinides are a series of 15 chemical elements from actinium (atomic number 89) to lawrencium (atomic number 103) in the periodic table. They are characterized by having valence electrons in the $5f$ orbitals. Most actinides are synthetic and radioactive, except for uranium and thorium, which occur naturally in significant amounts.
What are Lanthanides?
The lanthanides are another series of 15 chemical elements from lanthanum (atomic number 57) to lutetium (atomic number 71). They are characterized by having valence electrons in the $4f$ orbitals. Together, the lanthanides and actinides are often called the f-block elements because their distinguishing electrons are in the f orbital.
Analyzing the Given Options
Let's examine each option and determine its placement in the periodic table:
Lutetium (Lu): Lutetium has atomic number 71. It is the last element in the lanthanide series.
Curium (Cm): Curium has atomic number 96. It falls within the actinide series.
Ytterbium (Yb): Ytterbium has atomic number 70. It is a member of the lanthanide series.
Erbium (Er): Erbium has atomic number 68. It is a member of the lanthanide series.
Based on their atomic numbers and typical classification in the periodic table, we can summarize the options:
Element
Symbol
Atomic Number
Series
Lutetium
Lu
71
Lanthanide
Curium
Cm
96
Actinide
Ytterbium
Yb
70
Lanthanide
Erbium
Er
68
Lanthanide
Comparing the options to the definition of actinides, Curium (Cm) is the only element listed that belongs to the actinide series.
Conclusion: Identifying the Actinide Element
By examining the location of each element in the periodic table and understanding the definition of the actinide series, we can confirm that Curium is the correct answer.
Revision Table: Actinide Elements Study
Concept
Key Point
Actinides
Elements Ac (89) to Lr (103). f-block elements. Mostly radioactive.
Lanthanides
Elements La (57) to Lu (71). f-block elements.
Curium (Cm)
Atomic Number 96. Located in the Actinide series.
Lutetium (Lu)
Atomic Number 71. Located in the Lanthanide series.
Ytterbium (Yb)
Atomic Number 70. Located in the Lanthanide series.
Erbium (Er)
Atomic Number 68. Located in the Lanthanide series.
Additional Information: Properties of Actinides
Actinide elements have several notable properties:
All actinides are radioactive, meaning they undergo radioactive decay.
Many actinides, particularly those with higher atomic numbers, are synthetic, meaning they are not found naturally on Earth and are produced in laboratories or nuclear reactors.
Actinides are metals. They are typically dense with distinctive crystal structures.
They exhibit variable oxidation states, which is more pronounced than in the lanthanides. Common oxidation states include +3, +4, +5, and +6.
They are used in various applications, including nuclear fuel (like Uranium and Plutonium) and smoke detectors (like Americium).
Understanding the distinction between lanthanides and actinides is crucial for studying the properties of f-block elements.
Paper & answer key PDF ↗ Question 38archived
In February 2019, Flight Lieutenant________ created history by becoming the first Indian woman flight engineer.
- A
Bhawana Seth
- B
Mohana Singh
- C
Hina Jaiswal
- D
Anjali Gupta
Show answer
C. Hina JaiswalUnderstanding the First Indian Woman Flight Engineer
The question asks about a significant achievement in the history of the Indian Air Force (IAF) in February 2019. Specifically, it wants to identify the first Indian woman to qualify as a flight engineer.
Becoming a flight engineer is a demanding role that requires specialized training in aircraft systems. This achievement marked a major step towards greater gender equality in the Indian defence forces, opening up new roles for women.
Identifying the Pioneer Woman Flight Engineer
In February 2019, the Indian Air Force announced that one of its officers had successfully completed the rigorous training to become the first woman flight engineer. This officer was part of the first batch of women officers commissioned into the flying branch in 2018, who were subsequently trained for specialized roles.
Let's look at the options provided:
Bhawana Seth
Mohana Singh
Hina Jaiswal
Anjali Gupta
Research confirms that Flight Lieutenant Hina Jaiswal created history by becoming the first Indian woman flight engineer in February 2019. She was commissioned into the IAF's engineering branch in 2015 and underwent the flight engineer course at Air Force Station Yelahanka.
What is a Flight Engineer?
A flight engineer is a member of an aircraft's flight crew. Their primary responsibility is to monitor and operate complex aircraft systems, ensuring the aircraft's airworthiness during flight. They are typically found on larger or older aircraft where the workload is too great for the pilots alone. The role involves:
Checking aircraft systems before, during, and after flight.
Monitoring engines, fuel, hydraulics, electrical systems, etc.
Troubleshooting and addressing technical issues in flight.
Assisting the pilots with managing aircraft performance.
Significance of the Achievement
Flight Lieutenant Hina Jaiswal's achievement is highly significant because it:
Broke barriers for women in technical and operational roles within the IAF.
Demonstrated that women can excel in demanding engineering and flying-related fields.
Paved the way for more women to take up flight engineering and other specialized roles in the future.
Considering the historical context and the official announcements made in February 2019, Flight Lieutenant Hina Jaiswal is the correct individual.
Conclusion based on Analysis
Based on the information, the first Indian woman flight engineer in February 2019 was Flight Lieutenant Hina Jaiswal.
Achievement
Individual
Year/Context
First Indian Woman Flight Engineer
Flight Lieutenant Hina Jaiswal
February 2019
First three Indian women fighter pilots
Flight Lieutenant Bhawana Kanth,
Flight Lieutenant Mohana Singh,
Flight Lieutenant Avani Chaturvedi
Commissioned 2016, operational roles later
Revision Table: Key Figures in Indian Air Force
Name
Significant Role/Achievement
Context
Flight Lieutenant Hina Jaiswal
First Indian Woman Flight Engineer
February 2019
Flight Lieutenant Bhawana Kanth
One of the first three Indian women fighter pilots
Commissioned 2016
Flight Lieutenant Mohana Singh
One of the first three Indian women fighter pilots
Commissioned 2016
Flight Lieutenant Avani Chaturvedi
One of the first three Indian women fighter pilots
Commissioned 2016
Anjali Gupta
First woman officer court-martialed in the IAF
Mentioned in media reports regarding disciplinary issues
Additional Information: Women in Indian Air Force
The induction of women into various branches of the Indian Air Force has evolved significantly over the years. Initially inducted only into ground duty branches, women were later allowed into flying branches such as transport and helicopter streams. The milestone of inducting women into the fighter stream in 2016, and subsequent roles like flight engineers in 2019, highlights the IAF's commitment to providing equal opportunities based on merit and capability.
Women officers undergo the same rigorous training as their male counterparts.
The roles available to women are gradually expanding across all three wings of the Indian Armed Forces.
These steps are crucial for leveraging the full potential of India's human resources in defence.
The success of officers like Flight Lieutenant Hina Jaiswal serves as an inspiration for future generations of women aspiring to join the Indian Air Force in challenging roles.
Paper & answer key PDF ↗ Question 39archived
One of the prominent Buddhist structures in India, ________ Stupa at Sarnath was constructed by the great Mauryan king, Ashoka.
- A
Dhauli
- B
Dhamekh
- C
Bharhut
- D
Lalitgiri
Show answer
B. DhamekhUnderstanding Ancient Indian Buddhist Structures
The question asks to identify a prominent Buddhist structure in India, specifically a Stupa located at Sarnath, which was constructed by the great Mauryan king, Ashoka. Sarnath is a significant site in Buddhist history as it is where the Buddha gave his first sermon.
Analyzing the Options for the Sarnath Stupa
Let's examine the provided options:
Dhauli: Dhauli is located in Odisha and is known for Ashokan rock edicts, not a prominent stupa built by Ashoka at Sarnath.
Dhamekh: The Dhamekh Stupa is indeed located at Sarnath, Uttar Pradesh, and is a significant Buddhist structure believed to have been built by Emperor Ashoka in 249 BCE, later rebuilt and enlarged. It marks the spot where the Buddha is said to have delivered his first sermon.
Bharhut: Bharhut is a site in Madhya Pradesh famous for its stupa, but the Bharhut Stupa and its gateways are generally attributed to the Shunga period, not Ashoka or Sarnath.
Lalitgiri: Lalitgiri is part of the "Diamond Triangle" of Buddhist sites in Odisha (along with Ratnagiri and Udayagiri). While it has important stupas and monasteries, it is not the prominent stupa in Sarnath built by Ashoka.
Based on historical and archaeological evidence, the Dhamekh Stupa fits the description of a prominent Buddhist structure at Sarnath constructed by Emperor Ashoka.
The Significance of Dhamekh Stupa, Sarnath
The Dhamekh Stupa is a massive stone and brick structure. It is cylindrical and stands about 43.6 meters high with a diameter of 28 meters. Its construction is significant because it is associated with Ashoka, who played a crucial role in promoting Buddhism across his vast empire. The presence of Ashokan pillars with edicts at Sarnath further underscores the connection of Ashoka to this important Buddhist site. The Dhamekh Stupa represents the Dharmachakra Pravartana, the turning of the Wheel of Dharma, Buddha's first teaching.
Comparison of Stupas/Sites
Stupa/Site
Location
Associated Period/Builder
Significance
Dhamekh Stupa
Sarnath, Uttar Pradesh
Ashoka (Mauryan), later additions
Marks site of Buddha's first sermon
Dhauli
Odisha
Ashoka (Mauryan)
Rock Edicts
Bharhut Stupa
Madhya Pradesh
Shunga period
Stupa and gateways known for carvings
Lalitgiri
Odisha
Various periods (Brahminical, Buddhist)
Buddhist complex (stupas, monasteries, sculptures)
Therefore, the correct answer is the Dhamekh Stupa at Sarnath.
Revision Table: Important Buddhist Sites
Key Buddhist Archaeological Sites in India
Site
Location
Key Structures
Historical Significance
Sarnath
Uttar Pradesh
Dhamekh Stupa, Ashoka Pillar, Mulagandhakuti Vihara
First Sermon of Buddha (Dharmachakra Pravartana)
Bodh Gaya
Bihar
Mahabodhi Temple, Bodhi Tree
Site of Buddha's enlightenment
Sanchi
Madhya Pradesh
Great Stupa (Stupa 1), Ashoka Pillar
Major centre of Buddhist art and architecture from Mauryan period onwards
Kushinagar
Uttar Pradesh
Mahaparinirvana Temple, Ramabhar Stupa
Site of Buddha's Mahaparinirvana (death)
Additional Information on Ashoka and Buddhist Stupas
Emperor Ashoka (reigned c. 268 to 232 BCE) is renowned for his conversion to Buddhism and his efforts to spread the religion throughout his vast Mauryan Empire and beyond. He is credited with building numerous stupas and pillars across India, many inscribed with his edicts promoting Dharma. Stupas are dome-shaped structures used as a reliquary or commemorative monument associated with Buddhism. Initially, they were simple mounds but evolved into complex architectural forms under Ashoka and later dynasties. The Dhamekh Stupa is a testament to Ashoka's architectural patronage and the importance of Sarnath in the Buddhist world.
Paper & answer key PDF ↗ Question 40archived
____ died in 1605, nearly 50 years after his ascension to the throne. He was buried outside of Agra at Sikandra.
- A
Jahangir
- B
Aurangzeb
- C
Akbar
- D
Shah Jahan
Show answer
C. AkbarCorrect answer: Akbar
Comparing this information with the question's details confirms that Akbar is the correct answer.
Paper & answer key PDF ↗ Question 41archived
In the periodic table, Mendeleev could NOT assign a correct position to _________.
- A
Carbon
- B
Nitrogen
- C
Hydrogen
- D
Oxygen
Show answer
C. HydrogenUnderstanding Mendeleev's Periodic Table and Element Placement
Dmitri Mendeleev organized the elements known in his time into a periodic table. His primary basis for organization was the atomic mass of the elements and their chemical properties. He arranged elements in increasing order of atomic mass and grouped together elements with similar properties.
The Challenge of Placing Hydrogen in Mendeleev's Table
While Mendeleev's periodic table was a remarkable achievement, it did have some limitations. One significant challenge he faced was determining the correct position for the element hydrogen. Hydrogen is a unique element with properties that align somewhat with two different groups of elements.
Hydrogen has a valency of 1, similar to alkali metals (Group 1 elements like Lithium, Sodium, Potassium). Like alkali metals, hydrogen can lose one electron to form a positive ion, $\text{H}^+$.
Hydrogen also shows similarities with halogens (Group 17 elements like Fluorine, Chlorine, Bromine). Like halogens, hydrogen exists as a diatomic molecule ($\text{H}_2$) and can gain one electron to form a negative ion, $\text{H}^-$.
Due to these dual similarities, it was difficult to assign a single, definitive position to hydrogen based solely on its atomic mass and typical group properties within Mendeleev's framework.
Why Other Options Were Placed Correctly
Let's consider the other elements listed in the options:
Carbon: Carbon (atomic mass ≈ 12) was placed in Group 4 in Mendeleev's table, consistent with its valency of 4 and formation of oxides ($\text{CO}_2$). Its properties fit well within this group.
Nitrogen: Nitrogen (atomic mass ≈ 14) was placed in Group 5, corresponding to its valency and typical compounds like oxides ($\text{N}_2\text{O}_5$) and hydrides ($\text{NH}_3$). Its position was well-defined.
Oxygen: Oxygen (atomic mass ≈ 16) was placed in Group 6, fitting its valency of 2 and formation of oxides ($\text{H}_2\text{O}$, $\text{CO}_2$). Its placement was straightforward.
These elements had properties and atomic masses that clearly aligned them with specific groups in Mendeleev's arrangement, unlike hydrogen which presented an ambiguity.
Conclusion on Mendeleev's Periodic Table Position Problem
Therefore, among the given options, hydrogen was the element that Mendeleev could not assign a correct position to definitively because of its unique properties that resembled both alkali metals and halogens.
Element
Position Challenge in Mendeleev's Table
Hydrogen
Could not be assigned a single correct position due to similarities with both alkali metals (Group 1) and halogens (Group 17).
Carbon
Placed correctly in Group 4 based on valency and properties.
Nitrogen
Placed correctly in Group 5 based on valency and properties.
Oxygen
Placed correctly in Group 6 based on valency and properties.
Revision Table: Mendeleev's Periodic Table Issues
Aspect
Details
Basis of Classification
Atomic mass and chemical properties.
Successes
Prediction of properties of undiscovered elements (e.g., Eka-Aluminium/Gallium). Organized known elements logically.
Limitations (including the question's topic)
Position of hydrogen (similarity to Group 1 and Group 17). Placement of isotopes (not applicable in his time but a conceptual issue later). Anomalous pairs (elements with higher atomic mass placed before elements with lower atomic mass to fit properties, e.g., Argon before Potassium).
Additional Information: Modern Periodic Table
The Modern Periodic Table, developed based on the work of Henry Moseley, arranges elements by atomic number instead of atomic mass. This resolved many of the anomalies in Mendeleev's table, including the placement of isotopes and anomalous pairs.
In the modern table:
Hydrogen is placed in Group 1, Period 1, above the alkali metals, primarily because it has one valence electron ($\text{1s}^1$). However, its unique properties are still noted, and it is sometimes shown separately.
The problem of anomalous pairs was resolved as elements are arranged by increasing atomic number, which consistently reflects the properties better than atomic mass.
Isotopes have the same atomic number and chemical properties, so they fit into the same position in the modern table, unlike in Mendeleev's table where variations in atomic mass might cause issues.
Paper & answer key PDF ↗ Question 42archived
Superstats, a new platform to analyse the game of cricket, comprises of three metrics. Which of the following is NOT one of them?
- A
Forecaster
- B
Score Index
- C
Luck Index
- D
Smart Stats
Show answer
B. Score IndexSuperstats is an innovative platform developed to provide deeper insights into the game of cricket through advanced analytics. It uses a combination of data science and statistical modeling to evaluate player performance, team strategies, and match outcomes in a more nuanced way than traditional metrics.
The platform is built upon three key metrics designed to capture different aspects of the game. Understanding these metrics helps in appreciating the analytical power of Superstats.
Understanding Superstats Cricket Metrics
The three core metrics that form the basis of the Superstats platform are:
Forecaster: This metric predicts potential outcomes in the game, such as likely scores, required run rates, and win probabilities, based on the current situation, historical data, and ground conditions.
Luck Index: This metric attempts to quantify the element of luck in a player's performance or a match outcome. It tries to separate fortunate events (like a dropped catch or an edge going for four) from the player's actual skill and decision-making.
Smart Stats: These are context-specific metrics that provide deeper insights beyond traditional statistics like runs or wickets. They account for factors like the match situation, opposition, pitch conditions, and pressure levels to evaluate a player's performance more accurately in specific scenarios.
Analyzing the Options
Let's look at the given options in the context of the Superstats metrics:
Option
Part of Superstats?
Explanation
Forecaster
Yes
This is one of the core metrics used for predictions.
Score Index
No
This is not recognized as one of the three primary metrics of the Superstats platform. While scores are fundamental in cricket, 'Score Index' as a specific metric within Superstats is not listed among its core components.
Luck Index
Yes
This is one of the core metrics used to assess the influence of fortune.
Smart Stats
Yes
These are one of the core metrics providing contextual performance analysis.
Based on the known components of the Superstats platform (Forecaster, Luck Index, and Smart Stats), the option that is NOT one of these metrics is Score Index.
Conclusion on Superstats Metrics
The question asks which of the given options is NOT one of the three metrics comprising Superstats. By identifying the actual metrics (Forecaster, Luck Index, and Smart Stats), we can determine the option that does not belong to this set.
The option 'Score Index' is not one of the three core metrics of the Superstats platform for cricket analysis.
Revision Table: Superstats Key Metrics
Superstats Metric
Brief Description
Forecaster
Predicts match outcomes, scores, probabilities based on current situation.
Luck Index
Quantifies the impact of luck on performance or outcomes.
Smart Stats
Provides contextual performance analysis accounting for match situation and conditions.
Additional Information on Cricket Analytics
Cricket analytics platforms like Superstats aim to move beyond traditional statistics to offer more insightful analysis. They use various techniques including data mining, statistical modeling, and machine learning to process vast amounts of data generated during matches.
Traditional metrics (e.g., Batting Average, Strike Rate, Economy Rate) are foundational but often lack context.
Advanced metrics incorporate factors like pitch conditions, pressure situations, opposition strength, and match phase (powerplay, middle overs, death overs).
These tools are used by teams, coaches, commentators, and fans to gain a deeper understanding of player performance, strategy effectiveness, and match dynamics.
Platforms like Superstats represent the growing integration of data science into sports, enhancing analysis and fan engagement.
Paper & answer key PDF ↗ Question 43archived
__________ married Mehr-un-Nisa whom he gave the title of 'Nur Jahan' (light of the world).
- A
Akbar
- B
Jahangir
- C
Aurangzeb
- D
Shah Jahan
Show answer
B. JahangirUnderstanding the Question: Mughal Emperors and Their Consorts
The question asks us to identify the Mughal emperor who married Mehr-un-Nisa and subsequently gave her the famous title of 'Nur Jahan'. This is a key detail in Mughal history, related to the lives of prominent royal figures.
Analyzing the Options
We are given four options, all of whom were significant Mughal emperors:
Akbar
Jahangir
Aurangzeb
Shah Jahan
To find the correct answer, we need to recall which of these emperors was married to Mehr-un-Nisa, known as Nur Jahan.
Identifying the Emperor Married to Nur Jahan
Historically, Nur Jahan (born Mehr-un-Nisa) was one of the most influential empresses of the Mughal Empire. Her marriage to a specific emperor significantly impacted the court and administration during his reign.
Akbar: Akbar was the grandfather of Shah Jahan and father of Jahangir. While he had many wives, Mehr-un-Nisa was not among them during his lifetime.
Jahangir: Prince Salim, later Emperor Jahangir, married Mehr-un-Nisa in 1611. After their marriage, he bestowed upon her the title 'Nur Mahal' (Light of the Palace), which was later changed to 'Nur Jahan' (Light of the World). Nur Jahan became a very powerful figure in Jahangir's court.
Aurangzeb: Aurangzeb was the great-grandson of Akbar, grandson of Jahangir, and son of Shah Jahan. He reigned much later than the period relevant to Nur Jahan.
Shah Jahan: Shah Jahan was the son of Jahangir and the famous Mumtaz Mahal (for whom the Taj Mahal was built). He was not married to Nur Jahan; Nur Jahan was his stepmother.
Conclusion: The Emperor Who Married Mehr-un-Nisa
Based on historical records, it is clear that Emperor Jahangir was the one who married Mehr-un-Nisa and gave her the title 'Nur Jahan'. This makes option 2 the correct answer.
Emperor
Relationship with Nur Jahan
Akbar
Jahangir's father, Shah Jahan's grandfather, Nur Jahan's father-in-law (after her marriage to Jahangir)
Jahangir
Married to Mehr-un-Nisa (Nur Jahan)
Aurangzeb
Jahangir's grandson, ruled much later
Shah Jahan
Jahangir's son, Nur Jahan's stepson
Revision Table: Key Mughal Marriages
Emperor
Notable Consort
Title Given
Relationship to Nur Jahan
Jahangir
Mehr-un-Nisa
Nur Jahan (Light of the World)
Herself
Shah Jahan
Arjumand Banu Begum
Mumtaz Mahal (Ornament of the Palace)
Daughter-in-law of Nur Jahan (Mumtaz Mahal was married to Nur Jahan's stepson, Shah Jahan)
Additional Information: The Influence of Nur Jahan
Nur Jahan was not just an empress consort; she was a highly capable woman who wielded significant political influence during Jahangir's reign, especially as his health declined. She was involved in administrative decisions, issued farmans (royal decrees), and coins were even struck in her name. Her period of influence is often referred to as the 'Nur Jahan Junta' or 'Nur Jahan Circle', comprising her family members who held important positions. Her prominence in the Mughal court highlights the potential for women to exercise power, even within the patriarchal structure of the empire.
Paper & answer key PDF ↗ Question 44archived
Law of octaves says that if the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of ______ elements.
- A
5
- B
9
- C
10
- D
7
Show answer
D. 7Let's understand Newlands' Law of Octaves, which attempted to classify chemical elements based on their properties.
Understanding Newlands' Law of Octaves for Chemical Elements
In 1866, John Newlands, an English chemist, proposed a way to arrange the known chemical elements. At that time, about 56 elements were known. He arranged these elements in order of increasing atomic weight. While arranging them, he observed a peculiar pattern in their physical and chemical properties.
The Observation: Repeating Properties of Elements
Newlands noticed that the properties of the eighth element were similar to the properties of the first element, just like the notes in a musical octave repeat after the seventh note. He called this observation the 'Law of Octaves'.
According to this law, when elements are arranged in increasing order of atomic weight, the properties of every eighth element are similar to the properties of the first element. This means that the similarity in properties occurs after an interval of seven elements.
Illustrating the Law of Octaves
Newlands arranged elements in rows of seven, like this:
Note
Do
Re
Mi
Fa
So
La
Ti
Element
Li
Be
B
C
N
O
F
Element
Na
Mg
Al
Si
P
S
Cl
Element
K
Ca
Cr
Ti
Mn
Fe
Co & Ni
Element
Cu
Zn
Y
In
As
Se
Br
...
...
...
...
...
...
...
...
In this arrangement, Lithium (Li) is the first element in the first row. Sodium (Na), which is the eighth element (after Li, Be, B, C, N, O, F), is placed below Lithium and has properties similar to Lithium. Similarly, Potassium (K), the eighth element after Sodium, is placed below Lithium and Sodium, and its properties are also similar to them.
Limitations of Newlands' Law of Octaves
While this law worked reasonably well for the lighter elements up to Calcium, it failed for heavier elements. New elements discovered later did not fit into this pattern. Also, Newlands placed some elements with different properties in the same column and some elements with similar properties in different columns (e.g., Co and Ni were placed together). Despite its limitations, the Law of Octaves was an important early step towards the periodic classification of elements.
Conclusion on Element Property Repetition
According to Newlands' Law of Octaves, properties of chemical elements arranged by increasing atomic weight repeat after an interval of seven elements. This means the 8th element shows similar properties to the 1st, the 9th to the 2nd, and so on, within a series.
Revision Table: Key Facts on Law of Octaves
Concept
Details
Proposed by
John Newlands
Year
1866
Basis of Arrangement
Increasing atomic weight
Observation
Properties of every 8th element are similar to the 1st
Interval of Similarity
After 7 elements
Analogy
Musical octaves
Applicable Up To
Calcium
Additional Information: Evolution of Periodic Classification of Elements
Newlands' Law of Octaves was one of the early attempts to classify elements. Later, other scientists made significant contributions:
Döbereiner's Triads: Johann Wolfgang Döbereiner grouped elements in sets of three (triads) based on similar properties. He noted that the atomic weight of the middle element was roughly the average of the other two.
Mendeleev's Periodic Law: Dmitri Mendeleev created a more comprehensive periodic table. His law stated that the properties of elements are a periodic function of their atomic weights. He even left gaps for undiscovered elements and predicted their properties.
Modern Periodic Law: The modern periodic table is based on the Modern Periodic Law, proposed by Henry Moseley. This law states that the properties of elements are a periodic function of their atomic numbers (not atomic weights). Arranging elements by atomic number resolved many anomalies in Mendeleev's table.
Each of these laws built upon previous attempts, leading to the periodic table used today, which accurately reflects the periodic recurrence of chemical and physical properties of elements.
Paper & answer key PDF ↗ Question 45archived
Who among the following gave the 'Law of Octaves'?
- A
Dobereiner
- B
Lavoisier
- C
Newlands
- D
Mendeleev
Show answer
C. NewlandsUnderstanding the Law of Octaves
This question asks us to identify the scientist who formulated the 'Law of Octaves', which is a concept related to the early attempts at classifying chemical elements.
John Newlands' Contribution: The Law of Octaves
The 'Law of Octaves' was proposed by the English chemist John Newlands in 1865. He arranged the elements known at that time in order of their increasing atomic weights. Newlands observed a recurring pattern: every eighth element in this sequence possessed similar chemical and physical properties to the first element. He likened this repetition of properties to the pattern of notes in a musical octave, where the eighth note is the same as the first. For example, Lithium is the first element in a sequence, and the eighth element after it is Sodium (Na). Both Lithium and Sodium are highly reactive alkali metals.
Newlands' Law of Octaves was a pioneering step towards understanding the periodicity of element properties. It suggested that there was an underlying order in the elements, which paved the way for later, more comprehensive systems like the Periodic Table. However, his law faced limitations, including its applicability only to lighter elements and its inability to account for undiscovered elements.
Key Scientists in Element Classification
To clarify why John Newlands is the correct answer, let's briefly look at the contributions of the other scientists mentioned:
Dobereiner: Johann Wolfgang Döbereiner developed the concept of 'Triads'. He grouped elements in threes based on similar properties, noting that the atomic weight of the middle element was approximately the average of the other two.
Lavoisier: Antoine Lavoisier, considered a foundational figure in chemistry, compiled an early list of elements. While important, his work did not involve the pattern observed in the 'Law of Octaves'.
Mendeleev: Dmitri Mendeleev is famous for creating the Periodic Table, arranging elements by atomic weight and predicting the properties of missing elements. His system was more advanced and widely accepted than Newlands' earlier law.
Final Identification
Therefore, the scientist who gave the 'Law of Octaves' based on the repeating pattern of properties every eighth element is John Newlands.
Paper & answer key PDF ↗ Question 46archived
Indian origin campaigner _____ was named UK’s Most Influential Black Person of the Year on 25 October 2017.
- A
David Olusoga
- B
Gina Miller
- C
Jonathan Marland
- D
Priti Patel
Show answer
B. Gina MillerUK's Most Influential Black Person Award 2017
The question asks about the Indian-origin campaigner who received the title of UK's Most Influential Black Person on October 25, 2017.
This prestigious recognition is part of the annual Powerlist, which ranks the 100 most influential people of African or Caribbean descent in the United Kingdom.
Analyzing the Options
Let's look at the provided options:
David Olusoga: A well-known British-Nigerian historian, writer, and broadcaster. While highly influential, he was not the person named Most Influential Black Person in the UK in 2017 on October 25th for that year's Powerlist top spot.
Gina Miller: An investment manager and campaigner known for her legal challenges against the UK government regarding Brexit. She is of Indian and Guyanese descent and is a prominent figure in UK public life.
Jonathan Marland: A British businessman and Conservative politician. He is not of African or Caribbean descent and therefore would not be eligible for this specific award focusing on the Black community's influence.
Priti Patel: A British politician who served as Home Secretary. She is of Indian Gujarati descent but is primarily known for her political career rather than being recognized as the Most Influential Black Person by this specific award/list.
Identifying the Correct Individual
Based on reports from October 2017, Indian-origin campaigner Gina Miller was indeed named the UK's Most Influential Black Person. Her prominence significantly rose due to her successful legal challenges requiring parliamentary approval for the UK government to trigger Article 50 to leave the European Union. Her campaigning work and impact on national politics led to her topping the Powerlist that year, recognizing her significant influence.
Therefore, Gina Miller fits the description of the Indian-origin campaigner who was named UK's Most Influential Black Person on October 25, 2017.
Revision Table: Key Details
Detail
Information
Award/Recognition
UK's Most Influential Black Person
Year
2017
Date Announced
October 25, 2017
Recipient
Gina Miller
Origin/Background
Indian-origin campaigner
Additional Information: The Powerlist
The Powerlist is an annual publication profiling the 100 most influential people of African or African Caribbean heritage in the United Kingdom. It was established in 2007. The list covers various sectors including politics, business, technology, arts, science, and social activism. Topping the Powerlist is considered a significant acknowledgment of an individual's impact and influence within the UK.
Gina Miller's inclusion and top ranking in 2017 highlighted the impact of her legal challenges and campaigning on national discourse and policy. It underscored the diverse backgrounds of individuals recognized on the list.
Paper & answer key PDF ↗ Question 47archived
The power to summon the Houses of the Parliament is vested with the ______.
- A
Speaker
- B
Vice President
- C
Prime Minister
- D
President
Show answer
D. PresidentUnderstanding the Power to Summon Parliament
The question asks about the authority responsible for summoning the Houses of the Parliament. In India, the Parliament consists of the President and the two Houses: the Lok Sabha (House of the People) and the Rajya Sabha (Council of States). Summoning Parliament refers to calling its sessions to begin.
Who Summons the Houses of Parliament?
According to the Constitution of India, the power to summon each House of Parliament is vested with the President of India. Article 85(1) of the Constitution explicitly states that the President shall from time to time summon each House of Parliament to meet at such time and place as he thinks fit, but six months shall not intervene between its last sitting in one session and the date appointed for its first sitting in the next session.
Therefore, the President is the constitutional head who formally calls the sessions of both the Lok Sabha and the Rajya Sabha.
Examining Other Options
Speaker: The Speaker is the presiding officer of the Lok Sabha. Their role is to conduct proceedings in the Lok Sabha, maintain order, and interpret rules. The Speaker does not have the power to summon Parliament sessions.
Vice President: The Vice President of India is the ex-officio Chairman of the Rajya Sabha. They preside over the sessions of the Rajya Sabha. Like the Speaker, the Vice President does not have the power to summon Parliament sessions.
Prime Minister: The Prime Minister is the head of the government and the leader of the Council of Ministers. The Prime Minister and the Council of Ministers advise the President on summoning Parliament. However, the formal constitutional power to summon is with the President, who acts on the aid and advice of the Council of Ministers headed by the Prime Minister.
Comparison of Roles Related to Parliament Sessions
Official
Primary Role Related to Parliament
Power to Summon Sessions?
President
Constitutional Head; Integral part of Parliament
Yes (Formally summons both Houses as per Article 85(1))
Speaker
Presiding Officer of Lok Sabha
No
Vice President
Ex-officio Chairman of Rajya Sabha; Presiding Officer of Rajya Sabha
No
Prime Minister
Head of Government; Advises the President
No (Advises, but doesn't formally summon)
Based on the constitutional provisions, the power to formally summon the Houses of the Parliament is vested exclusively with the President of India.
Revision Table: Key Facts on Summoning Parliament
Aspect
Detail
Authority for Summoning
President of India
Constitutional Article
Article 85(1)
Requirement
Maximum 6 months between last sitting of one session and first sitting of the next
Houses Summoned
Lok Sabha and Rajya Sabha
Basis of President's Action
On the aid and advice of the Council of Ministers led by the Prime Minister
Additional Information: Parliamentary Sessions in India
The summoning power is crucial for ensuring that Parliament meets regularly to discharge its legislative and oversight functions. There are typically three sessions in a year:
Budget Session: Usually held from February to May.
Monsoon Session: Usually held from July to September.
Winter Session: Usually held from November to December.
While the President formally summons Parliament, the decision on the dates and duration of sessions is taken by the Cabinet Committee on Parliamentary Affairs, which consists of senior ministers and is chaired by the Minister of Parliamentary Affairs (or sometimes the Home Minister). This recommendation is then forwarded to the President for formal approval and issuance of the summons.
The President also has the power to prorogue (terminate a session) and dissolve the Lok Sabha.
Paper & answer key PDF ↗ Question 48archived
The Parliament of India consists of ______.
- A
House of the People and Council of States
- B
President, House of the People and Council of States
- C
House of the People
- D
Council of States
Show answer
B. President, House of the People and Council of StatesUnderstanding the Composition of the Parliament of India
The Parliament of India is the supreme legislative body of the Republic of India. It is a bicameral legislature, meaning it has two houses, but its composition is more than just the two houses.
According to the Constitution of India, the Parliament consists of the following three parts:
The President of India
The House of the People (Lok Sabha)
The Council of States (Rajya Sabha)
Components of the Indian Parliament
Let's look at each component in detail:
The President of India: Although the President is not a member of either House of Parliament, they are an integral part of the Parliament. The President performs several key functions related to the Parliament, such as summoning and proroguing the Houses, dissolving the Lok Sabha, and giving assent to Bills passed by the Houses, without which a Bill cannot become a law.
The House of the People (Lok Sabha): This is the directly elected chamber of the Parliament. Members of the Lok Sabha are elected directly by the people through general elections. It represents the people of India as a whole.
The Council of States (Rajya Sabha): This is the indirectly elected chamber of the Parliament. Members of the Rajya Sabha are elected by the elected members of the Legislative Assemblies of the States and the Union Territories. It represents the states and union territories of the Indian Union.
Analyzing the Options
Based on the structure of the Parliament of India, let's evaluate the given options:
Option 1: <p>House of the People and Council of States </p> - This option only includes the two houses but omits the President, who is a crucial part of the Parliament. Therefore, this is incorrect.
Option 2: <p>President, House of the People and Council of States</p> - This option correctly lists all three components: the President, the House of the People, and the Council of States. This aligns with the constitutional definition of the Parliament of India.
Option 3: <p>House of the People</p> - This option only includes one house (Lok Sabha) and is incomplete. Therefore, this is incorrect.
Option 4: <p>Council of States</p> - This option only includes one house (Rajya Sabha) and is incomplete. Therefore, this is incorrect.
Thus, the Parliament of India is constituted by the President, the House of the People, and the Council of States.
Revision Table: Parliament of India Components
Component
Role in Parliament
President
Integral part; summons, prorogues, dissolves Lok Sabha, gives assent to Bills
House of the People (Lok Sabha)
Directly elected chamber; represents the people
Council of States (Rajya Sabha)
Indirectly elected chamber; represents states and union territories
Additional Information on Indian Parliament
The Indian Parliament is a powerful institution that performs legislative, executive oversight, financial, constituent, and judicial functions. The Lok Sabha and Rajya Sabha have different powers, although in many legislative matters, their powers are co-equal. However, the Lok Sabha holds more power in matters concerning the budget (Money Bills), and the Council of Ministers is collectively responsible to the Lok Sabha.
The inclusion of the President as a part of the Parliament highlights the Westminster model adapted in India, where the Head of State (President) is formally part of the legislature, even if their role is largely ceremonial in giving assent and formalizing parliamentary decisions.
Paper & answer key PDF ↗ Question 49archived
Swaroop Rawal, an Indian teacher at Lavad Primary School in ________ was in the running for the prestigious Global Teacher Prize 2019 which honours the world’s best teacher.
- A
Kerala
- B
Tamil Nadu
- C
Maharashtra
- D
Gujarat
Show answer
D. GujaratUnderstanding the Global Teacher Prize Nominee Swaroop Rawal
The question asks about the location of Lavad Primary School where Indian teacher Swaroop Rawal, a nominee for the prestigious Global Teacher Prize 2019, taught. This prize recognizes outstanding teachers who have made significant contributions to their profession.
Identifying Swaroop Rawal's Teaching Location
Swaroop Rawal is a well-known educator from India who gained international recognition for her innovative teaching methods. She was indeed among the top 10 finalists for the Varkey Foundation's Global Teacher Prize in 2019. Her nomination brought attention to her work at a primary school in a specific Indian state.
Based on reports and official information regarding the Global Teacher Prize 2019 nominations, Swaroop Rawal taught at Lavad Primary School in the state of Gujarat, India.
Analyzing the Options
Let's look at the provided options:
Kerala: While Kerala has a strong education system and many excellent teachers, Swaroop Rawal's school mentioned in the context of the Global Teacher Prize 2019 nomination was not located here.
Tamil Nadu: Tamil Nadu is another state known for its focus on education, but Swaroop Rawal's school relevant to this nomination is not in Tamil Nadu.
Maharashtra: Maharashtra is home to many schools and educators, but Lavad Primary School, where Swaroop Rawal taught during her Global Teacher Prize nomination period, is not in Maharashtra.
Gujarat: Records indicate that Swaroop Rawal, a finalist for the Global Teacher Prize 2019, taught at Lavad Primary School, located in the state of Gujarat. Her work focusing on life skills education through drama was highlighted.
Conclusion on Swaroop Rawal's State
Therefore, the state where Swaroop Rawal taught at Lavad Primary School and was nominated for the Global Teacher Prize 2019 is Gujarat.
Teacher
Prize/Recognition
School
State
Swaroop Rawal
Global Teacher Prize 2019 (Finalist)
Lavad Primary School
Gujarat
Revision Table: Global Teacher Prize Key Facts
Aspect
Detail
Prize Name
Global Teacher Prize
Awarding Body
Varkey Foundation
Purpose
To recognize an exceptional teacher who has made an outstanding contribution to their profession.
Prize Amount
US $1 million
Year Swaroop Rawal was finalist
2019
Swaroop Rawal's Focus
Life skills education through drama.
Additional Information: Swaroop Rawal and Global Teacher Prize
Swaroop Rawal's nomination for the Global Teacher Prize highlighted the importance of life skills education in primary schools. She used innovative methods like drama to help students cope with stress and build confidence. Her work in Gujarat exemplifies dedication to improving student well-being and learning outcomes, making her a fitting candidate for global recognition in the teaching profession.
The Global Teacher Prize aims to raise the status of the teaching profession and inspire young people to consider teaching as a career. It is awarded annually to one exceptional teacher who has made significant strides in education.
Paper & answer key PDF ↗ Question 50archived
A nautical mile is equal to ______.
- A
2450 metres
- B
2000 metres
- C
1672 metres
- D
1852 metres
Show answer
D. 1852 metresUnderstanding the Nautical Mile Definition
The question asks for the equivalent length of a nautical mile in metres. A nautical mile is a unit of distance used in sea and air navigation.
What is a Nautical Mile?
A nautical mile is based on the Earth's coordinates. Historically, it was defined as one minute of latitude along any line of longitude. Because the Earth is not a perfect sphere (it's slightly flattened at the poles), a minute of latitude varies slightly from point to point. To standardise this, the international nautical mile was defined.
The international nautical mile is defined as exactly 1,852 metres. This definition was adopted by the International Hydrographic Conference in 1929 and later by the United States in 1954 and the United Kingdom in 1970.
Comparing Nautical Miles and Other Units
It's helpful to compare the nautical mile to other common units of distance:
Nautical Mile: Used in navigation (sea and air). Based on Earth's size and latitude.
Statute Mile: The standard mile used on land in some countries (like the US). It is equal to 5,280 feet or approximately 1,609.344 metres.
Kilometre: A unit of distance in the metric system, equal to 1,000 metres.
Here’s a quick comparison in metres:
Unit
Equivalent in Metres
1 Nautical Mile
1852 m
1 Statute Mile
$\approx$ 1609.344 m
1 Kilometre
1000 m
Analyzing the Options
Let's look at the given options and compare them to the standard definition of a nautical mile:
2450 metres: This value is significantly higher than a nautical mile.
2000 metres: This is also higher than the standard value.
1672 metres: This value is closer to a statute mile than a nautical mile.
1852 metres: This exactly matches the internationally accepted definition of a nautical mile.
Conclusion
Based on the international definition, a nautical mile is equal to 1852 metres. This unit is crucial for accurate navigation across water and air, allowing for consistent distance measurements related to the Earth's coordinates.
Revision Table: Nautical Mile Key Facts
Concept
Detail
Unit Name
Nautical Mile
Primary Use
Sea and Air Navigation
Standard Length
1852 metres
Basis
Historically, based on one minute of latitude
Related Unit (Land)
Statute Mile (approx. 1609.344 m)
Additional Information: Importance in Navigation and Nautical Charting
The nautical mile is fundamental in navigation. Navigational charts typically use latitude and longitude grids, making the minute-of-latitude basis of the nautical mile very convenient for measuring distances directly on the chart. For example, measuring one minute of latitude on a chart corresponds to one nautical mile. Ship and aircraft speeds are often measured in knots, where one knot is defined as one nautical mile per hour. This direct relationship simplifies calculations involving speed, distance, and time in navigation.
Understanding the precise length of a nautical mile is essential for calculating distances between ports, determining fuel requirements, and ensuring safe and accurate travel across oceans and through the air.
Paper & answer key PDF ↗ Question 51archived
Let O be the centre of a circle and AC be its diameter. BD is a chord intersecting AC at E. Point B is joined to C and D. If ∠BOC = 50° and ∠AOD = 110°, then ∠BEC = ?
- A
70°
- B
80°
- C
55°
- D
90°
Show answer
B. 80°Solving Circle Geometry Problems: Finding Angle BEC
Let's break down this geometry problem involving a circle, diameter, chord, and intersecting lines. We are given a circle with center O and diameter AC. A chord BD intersects the diameter AC at point E. We are provided with the measures of two central angles: ∠BOC = $50^\circ$ and ∠AOD = $110^\circ$. Our goal is to find the measure of ∠BEC.
Understanding the Given Information
O is the center of the circle.
AC is the diameter passing through O.
BD is a chord intersecting AC at E.
∠BOC = $50^\circ$. This is the central angle subtending arc BC.
∠AOD = $110^\circ$. This is the central angle subtending arc AD.
We need to find ∠BEC.
Approach 1: Using the Intersecting Chords Theorem
The angle formed by the intersection of two chords inside a circle is half the sum of the measures of the arcs intercepted by the angle and its vertically opposite angle.
In our case, the chords AC and BD intersect at E. The angle ∠BEC intercepts arc BC, and its vertically opposite angle ∠AED intercepts arc AD.
The formula for the angle formed by intersecting chords is:
$\angle\text{BEC} = \frac{1}{2} (\text{measure of arc BC} + \text{measure of arc AD})$
Calculating Arc Measures
The measure of a central angle is equal to the measure of the arc it subtends.
The central angle ∠BOC subtends arc BC. So, measure of arc BC = ∠BOC = $50^\circ$.
The central angle ∠AOD subtends arc AD. So, measure of arc AD = ∠AOD = $110^\circ$.
Applying the Theorem
Now, substitute the arc measures into the formula:
$\angle\text{BEC} = \frac{1}{2} (50^\circ + 110^\circ)$
$\angle\text{BEC} = \frac{1}{2} (160^\circ)$
$\angle\text{BEC} = 80^\circ$
Approach 2: Using Inscribed Angles and Triangle Properties
Alternatively, we can find ∠BEC by considering triangle BEC. The sum of angles in a triangle is $180^\circ$. So, ∠BEC = $180^\circ$ - ∠EBC - ∠ECB. We need to find ∠EBC (or ∠DBC) and ∠ECB (or ∠ACB).
Finding Other Arc Measures
AC is a diameter, which divides the circle into two semicircles, each measuring $180^\circ$.
Arc ADC = $180^\circ$. We know arc AD = $110^\circ$. Since arc ADC = arc AD + arc DC, we have $180^\circ = 110^\circ$ + arc DC. So, arc DC = $180^\circ - 110^\circ = 70^\circ$.
Arc ABC = $180^\circ$. We know arc BC = $50^\circ$. Since arc ABC = arc AB + arc BC, we have $180^\circ = \text{arc AB} + 50^\circ$. So, arc AB = $180^\circ - 50^\circ = 130^\circ$.
Let's verify the total circle measure: arc AB + arc BC + arc CD + arc DA = $130^\circ + 50^\circ + 70^\circ + 110^\circ = 360^\circ$. This is correct.
Calculating Inscribed Angles
An inscribed angle is half the measure of its intercepted arc.
∠ECB is the same as ∠ACB. This inscribed angle subtends arc AB. So, ∠ECB = $\frac{1}{2} \text{arc AB} = \frac{1}{2} (130^\circ) = 65^\circ$.
∠EBC is the same as ∠DBC. This inscribed angle subtends arc DC. So, ∠EBC = $\frac{1}{2} \text{arc DC} = \frac{1}{2} (70^\circ) = 35^\circ$.
Finding ∠BEC in Triangle BEC
In $\triangle$BEC, we have:
∠BEC = $180^\circ$ - (∠EBC + ∠ECB)
∠BEC = $180^\circ$ - ($35^\circ + 65^\circ$)
∠BEC = $180^\circ$ - $100^\circ$
∠BEC = $80^\circ$
Both approaches yield the same result, confirming the answer.
Conclusion
Using either the intersecting chords theorem or the properties of inscribed angles and triangles, we find that the measure of ∠BEC is $80^\circ$.
Given Angle
Intercepted Arc (Central)
∠BOC = $50^\circ$
Arc BC = $50^\circ$
∠AOD = $110^\circ$
Arc AD = $110^\circ$
Calculated Arc
Measure
Reason
Arc DC
$70^\circ$
Arc ADC = $180^\circ$ (semicircle), Arc DC = $180^\circ$ - Arc AD
Arc AB
$130^\circ$
Arc ABC = $180^\circ$ (semicircle), Arc AB = $180^\circ$ - Arc BC
Inscribed Angle
Intercepted Arc
Calculation
∠ACB (or ∠ECB)
Arc AB ($130^\circ$)
$\frac{1}{2} \times 130^\circ = 65^\circ$
∠DBC (or ∠EBC)
Arc DC ($70^\circ$)
$\frac{1}{2} \times 70^\circ = 35^\circ$
Revision Table: Circle Geometry Concepts
Concept
Description
Formula/Property
Central Angle
Angle formed by two radii at the center.
Central Angle = Measure of intercepted arc
Inscribed Angle
Angle formed by two chords with vertex on the circle circumference.
Inscribed Angle = $\frac{1}{2}$ Measure of intercepted arc
Angle by Intersecting Chords (Inside)
Angle formed by two chords intersecting inside the circle.
Angle = $\frac{1}{2}$ (Sum of intercepted arcs)
Angles in a Triangle
Sum of interior angles of any triangle.
Sum = $180^\circ$
Diameter
A chord passing through the center. Divides circle into two $180^\circ$ semicircles.
Arcs subtended by diameter sum to $180^\circ$
Additional Information: Related Circle Theorems
Beyond the concepts used here, circle geometry involves many other theorems that are useful for solving problems:
Angle in a Semicircle: The angle inscribed in a semicircle is always a right angle ($90^\circ$). If P is any point on the circumference of a circle with diameter AB, then $\angle\text{APB} = 90^\circ$.
Angles Subtended by the Same Arc: Inscribed angles that subtend the same arc from the same side of the chord are equal.
Cyclic Quadrilaterals: A quadrilateral whose all four vertices lie on the circumference of a circle is called a cyclic quadrilateral. The sum of opposite angles of a cyclic quadrilateral is $180^\circ$.
Tangent-Secant Theorem: Relates the lengths of a tangent segment and a secant segment from an external point.
Angle between Tangent and Chord: The angle between a tangent and a chord through the point of contact is equal to the angle in the alternate segment.
Understanding these theorems helps in tackling a wide variety of circle geometry questions. Always start by identifying the type of angles and lines involved (central angles, inscribed angles, chords, tangents, secants, diameters) and the arcs they relate to.
Paper & answer key PDF ↗ Question 52archived
What is the ratio of the mean proportional between 4.8 and 10.8 and the third proportional to 0.4 and 2.4?
- A
1 ∶ 2
- B
2 ∶ 1
- C
3 ∶ 2
- D
2 ∶ 3
Show answer
A. 1 ∶ 2Let's break down this problem step-by-step to find the ratio of the mean proportional between 4.8 and 10.8 and the third proportional to 0.4 and 2.4.
Understanding Proportionality Concepts
First, we need to understand what mean proportional and third proportional mean.
Mean Proportional: For two positive numbers, 'a' and 'c', the mean proportional 'b' is the number such that $\frac{a}{b} = \frac{b}{c}$. This implies $b^2 = ac$, so $b = \sqrt{ac}$. The mean proportional is essentially the geometric mean of the two numbers.
Third Proportional: For two numbers, 'a' and 'b', the third proportional 'c' is the number such that $\frac{a}{b} = \frac{b}{c}$. This implies $ac = b^2$, so $c = \frac{b^2}{a}$.
Calculating the Mean Proportional
We need to find the mean proportional between 4.8 and 10.8.
Let the mean proportional be $m$. Using the formula $m = \sqrt{ac}$, where $a = 4.8$ and $c = 10.8$:
$\begin{aligned} m &= \sqrt{4.8 \times 10.8} \\ &= \sqrt{\frac{48}{10} \times \frac{108}{10}} \\ &= \sqrt{\frac{48 \times 108}{100}}\end{aligned}$
Now, let's simplify the numbers inside the square root:
$48 = 16 \times 3$
$108 = 36 \times 3$
So, $48 \times 108 = (16 \times 3) \times (36 \times 3) = 16 \times 36 \times 9$
$\begin{aligned} m &= \sqrt{\frac{16 \times 36 \times 9}{100}} \\ &= \frac{\sqrt{16} \times \sqrt{36} \times \sqrt{9}}{\sqrt{100}} \\ &= \frac{4 \times 6 \times 3}{10} \\ &= \frac{72}{10} \\ m &= 7.2\end{aligned}$
The mean proportional between 4.8 and 10.8 is 7.2.
Calculating the Third Proportional
Next, we need to find the third proportional to 0.4 and 2.4.
Let the third proportional be $t$. Using the formula $t = \frac{b^2}{a}$, where $a = 0.4$ and $b = 2.4$:
$\begin{aligned} t &= \frac{(2.4)^2}{0.4} \\ &= \frac{2.4 \times 2.4}{0.4} \\ &= \frac{5.76}{0.4}\end{aligned}$
To simplify the division, multiply the numerator and denominator by 10:
$\begin{aligned} t &= \frac{5.76 \times 10}{0.4 \times 10} \\ &= \frac{57.6}{4} \\ t &= 14.4\end{aligned}$
The third proportional to 0.4 and 2.4 is 14.4.
Finding the Ratio
The question asks for the ratio of the mean proportional (7.2) and the third proportional (14.4).
Ratio = Mean Proportional : Third Proportional
Ratio = 7.2 : 14.4
To simplify the ratio, we can divide both numbers by 7.2 (since 14.4 is exactly twice 7.2, or 14.4 / 7.2 = 2).
Ratio = $\frac{7.2}{7.2} : \frac{14.4}{7.2}$
Ratio = 1 : 2
The ratio of the mean proportional between 4.8 and 10.8 and the third proportional to 0.4 and 2.4 is 1 : 2.
Concept
Numbers
Calculation
Result
Mean Proportional
4.8 and 10.8
$\sqrt{4.8 \times 10.8} = \sqrt{51.84}$
7.2
Third Proportional
0.4 and 2.4
$\frac{2.4^2}{0.4} = \frac{5.76}{0.4}$
14.4
Ratio
7.2 and 14.4
$7.2 : 14.4$
1 : 2
Revision Table: Ratio and Proportion Concepts
Term
Definition
Mathematical Relation
Example
Ratio
Comparison of two quantities of the same unit.
$a:b$ or $\frac{a}{b}$
Ratio of 10 apples to 5 oranges is $10:5 = 2:1$.
Proportion
An equality of two ratios.
$\frac{a}{b} = \frac{c}{d}$ (a, b, c, d are in proportion)
If $\frac{2}{4} = \frac{3}{6}$, then 2, 4, 3, 6 are in proportion.
Mean Proportional
The middle term when three numbers are in continuous proportion.
If $a, b, c$ are in continuous proportion, $\frac{a}{b} = \frac{b}{c}$, $b = \sqrt{ac}$
Mean proportional between 4 and 9 is $\sqrt{4 \times 9} = \sqrt{36} = 6$.
Third Proportional
The last term when three numbers are in continuous proportion, given the first two.
If $a, b, c$ are in continuous proportion, $\frac{a}{b} = \frac{b}{c}$, $c = \frac{b^2}{a}$
Third proportional to 2 and 4 is $\frac{4^2}{2} = \frac{16}{2} = 8$.
Additional Information: Proportionality
Proportionality is a fundamental concept in mathematics used to describe how quantities relate to each other. Ratios and proportions help us compare sizes and quantities, understand relationships, and solve various problems in geometry, physics, and everyday life.
Continuous Proportion: When three numbers a, b, and c are such that the ratio of the first to the second is equal to the ratio of the second to the third ($\frac{a}{b} = \frac{b}{c}$), they are said to be in continuous proportion. Here, b is the mean proportional, c is the third proportional to a and b, and a is the first proportional to b and c.
Fourth Proportional: For three numbers a, b, and c, the fourth proportional d is the number such that $\frac{a}{b} = \frac{c}{d}$. This is used when four numbers are in proportion.
Understanding these concepts is crucial for solving problems involving ratios and proportions. The calculation relies on setting up the correct proportion based on whether you need the mean, third, or fourth proportional.
Paper & answer key PDF ↗ Question 53archived
The speed of train A is 25 km/h more than the speed of train B. A takes 4 hours less time to travel a distance of 300 km than what train B takes to travel 250 km. What is the speed (in km/h) of A?
- A
50
- B
65
- C
60
- D
55
Show answer
A. 50Solving Train Speed Problems Using Time, Distance, and Speed
This problem involves two trains, A and B, with different speeds and distances traveled over different times. We are given relationships between their speeds and times and need to find the speed of train A.
Let's define the variables:
Let the speed of train B be $v_B$ km/h.
According to the question, the speed of train A is 25 km/h more than the speed of train B. So, the speed of train A is $v_A = v_B + 25$ km/h.
We know the relationship between time, distance, and speed:
Time = $\frac{\text{Distance}}{\text{Speed}}$
Now, let's calculate the time taken by each train based on the given information:
Train A travels a distance of 300 km. The time taken by train A ($t_A$) is:
$t_A = \frac{300 \text{ km}}{v_A \text{ km/h}} = \frac{300}{v_B + 25}$ hours
Train B travels a distance of 250 km. The time taken by train B ($t_B$) is:
$t_B = \frac{250 \text{ km}}{v_B \text{ km/h}} = \frac{250}{v_B}$ hours
The question states that train A takes 4 hours less time than train B to travel the specified distances. This gives us the equation:
$t_A = t_B - 4$
Substitute the expressions for $t_A$ and $t_B$ into this equation:
$\frac{300}{v_B + 25} = \frac{250}{v_B} - 4$
Now, we need to solve this equation for $v_B$. First, let's find a common denominator for the right side of the equation:
$\frac{250}{v_B} - 4 = \frac{250}{v_B} - \frac{4v_B}{v_B} = \frac{250 - 4v_B}{v_B}$
So the equation becomes:
$\frac{300}{v_B + 25} = \frac{250 - 4v_B}{v_B}$
Cross-multiply to eliminate the denominators:
$300 \times v_B = (250 - 4v_B) \times (v_B + 25)$
$300v_B = 250v_B + 250 \times 25 - 4v_B \times v_B - 4v_B \times 25$
$300v_B = 250v_B + 6250 - 4v_B^2 - 100v_B$
Combine like terms on the right side:
$300v_B = (250v_B - 100v_B) + 6250 - 4v_B^2$
$300v_B = 150v_B + 6250 - 4v_B^2$
Move all terms to one side to form a standard quadratic equation ($av_B^2 + bv_B + c = 0$):
$4v_B^2 + 300v_B - 150v_B - 6250 = 0$
$4v_B^2 + 150v_B - 6250 = 0$
We can divide the entire equation by 2 to simplify it:
$2v_B^2 + 75v_B - 3125 = 0$
Now, we solve this quadratic equation for $v_B$. We can use the quadratic formula, which for an equation $ax^2 + bx + c = 0$ is $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$. In our case, $a=2$, $b=75$, and $c=-3125$.
$v_B = \frac{-75 \pm \sqrt{75^2 - 4(2)(-3125)}}{2(2)}$
$v_B = \frac{-75 \pm \sqrt{5625 + 25000}}{4}$
$v_B = \frac{-75 \pm \sqrt{30625}}{4}$
The square root of 30625 is 175.
$v_B = \frac{-75 \pm 175}{4}$
We have two possible solutions for $v_B$:
$v_B = \frac{-75 + 175}{4} = \frac{100}{4} = 25$
$v_B = \frac{-75 - 175}{4} = \frac{-250}{4} = -62.5$
Since speed cannot be a negative value, we discard the second solution. Therefore, the speed of train B is $v_B = 25$ km/h.
The question asks for the speed of train A. We know that $v_A = v_B + 25$.
$v_A = 25 + 25 = 50$ km/h.
So, the speed of train A is 50 km/h.
Verification of Train Speeds and Times
Let's check if our calculated speeds satisfy the time condition:
Speed of A ($v_A$) = 50 km/h
Speed of B ($v_B$) = 25 km/h
Time for A to travel 300 km ($t_A$) = $\frac{300}{50} = 6$ hours.
Time for B to travel 250 km ($t_B$) = $\frac{250}{25} = 10$ hours.
Is $t_A = t_B - 4$? $6 = 10 - 4$. Yes, $6 = 6$. The condition is satisfied.
The speed of train A is 50 km/h.
Revision Table: Train Speed Calculation
Concept
Description
Formula Used
Speed Relation
A is 25 km/h faster than B
$v_A = v_B + 25$
Time for A
Time = Distance / Speed for A
$t_A = \frac{300}{v_A}$
Time for B
Time = Distance / Speed for B
$t_B = \frac{250}{v_B}$
Time Relation
A takes 4 hours less than B
$t_A = t_B - 4$
Quadratic Equation
Equation derived from time relation
$2v_B^2 + 75v_B - 3125 = 0$
Quadratic Formula
Method to solve the quadratic equation
$v_B = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$
Additional Information on Speed, Distance, Time, and Quadratic Equations
Speed, Distance, and Time Relationship:
The fundamental relationship between speed, distance, and time is:
$\text{Speed} = \frac{\text{Distance}}{\text{Time}}$
This can be rearranged to find distance or time:
$\text{Distance} = \text{Speed} \times \text{Time}$
$\text{Time} = \frac{\text{Distance}}{\text{Speed}}$
These formulas are essential for solving problems involving motion.
Quadratic Equations:
A quadratic equation is a polynomial equation of the second degree, meaning it contains at least one term where the variable is squared. The standard form is $ax^2 + bx + c = 0$, where $x$ is the variable, and $a$, $b$, and $c$ are coefficients, with $a \neq 0$.
Solving quadratic equations can be done by factoring, completing the square, or using the quadratic formula. The quadratic formula ($x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$) is a reliable method that works for any quadratic equation.
In word problems, quadratic equations often arise when dealing with relationships between variables like speed and time, as seen in this train problem. It's crucial to recognize that in physical contexts (like speed), negative solutions to the equation are usually not valid.
Paper & answer key PDF ↗ Question 54archived
The average production of type A cars during the five years is what percent of the total production of type C cars during the five years?
- A
22.4
- B
21.8
- C
20.6
- D
18.7
Show answer
A. 22.4Solving Car Production Data Questions
This problem requires us to analyze the provided table showing the production of different types of cars over five years and perform calculations to find a percentage.
Cars/Year
2012
2013
2014
2015
2016
A
46
53
56
58
67
B
50
65
67
66
72
C
43
54
55
47
51
D
47
52
61
65
74
E
48
58
63
64
67
We need to find the average production of type A cars during the five years and the total production of type C cars during the five years. Then, we will express the average production of type A cars as a percentage of the total production of type C cars.
Calculating Average Production of Type A Cars
To find the average production of type A cars over the five years (2012 to 2016), we sum the production figures for type A for each year and divide by the number of years, which is 5.
Production of type A cars in 2012, 2013, 2014, 2015, and 2016 are 46, 53, 56, 58, and 67 thousand respectively.
Total production of type A cars over five years:
\begin{itemize}
\item $46 + 53 + 56 + 58 + 67 = 280$ thousand cars
\end{itemize}
Average production of type A cars:
\begin{itemize}
\item $\text{Average} = \frac{\text{Total Production}}{\text{Number of Years}}$
\item $\text{Average} = \frac{280}{5} = 56$ thousand cars
\end{itemize}
So, the average production of type A cars during the five years is 56 thousand.
Calculating Total Production of Type C Cars
To find the total production of type C cars during the five years (2012 to 2016), we sum the production figures for type C for each year.
Production of type C cars in 2012, 2013, 2014, 2015, and 2016 are 43, 54, 55, 47, and 51 thousand respectively.
Total production of type C cars over five years:
\begin{itemize}
\item $43 + 54 + 55 + 47 + 51 = 250$ thousand cars
\end{itemize}
So, the total production of type C cars during the five years is 250 thousand.
Calculating the Required Percentage
We need to find what percentage the average production of type A cars is of the total production of type C cars.
Percentage = $\frac{\text{Average production of type A}}{\text{Total production of type C}} \times 100$
Substituting the calculated values:
Percentage = $\frac{56}{250} \times 100$
Percentage = $0.224 \times 100$
Percentage = $22.4$
Therefore, the average production of type A cars during the five years is 22.4% of the total production of type C cars during the five years.
Revision Table: Car Production Analysis
Let's summarize the key calculations:
Car Type
Years
Calculation
Result (thousand cars)
Description
A
2012-2016
Summing production for 5 years and dividing by 5
56
Average Production
C
2012-2016
Summing production for 5 years
250
Total Production
Percentage calculation summary:
\begin{itemize}
\item Average A production: 56
\item Total C production: 250
\item Percentage = $(56 / 250) \times 100 = 22.4\%$
\end{itemize}
Additional Information: Data Interpretation and Percentages
Data interpretation questions often involve analyzing tables, charts, or graphs to extract information and perform calculations like averages, totals, ratios, and percentages. Understanding how to calculate these values is crucial for solving such problems.
Average: The average (or mean) of a set of numbers is the sum of the numbers divided by the count of numbers. It gives a central value for the set.
Total: The total is simply the sum of all the values in a set.
Percentage: A percentage is a way of expressing a proportion out of 100. To find what percentage quantity X is of quantity Y, you calculate $\frac{X}{Y} \times 100$.
When working with data interpretation tables showing quantities over several categories or time periods, always read the labels and units carefully (e.g., "in thousands" in this case). Ensure you are using the correct data points for the required calculations.
Paper & answer key PDF ↗ Question 55archived
If an 11-digit number 5y5884805x6 is divisible by 72, then the value of √(xy) is? where the value of x should be maximum∶
- A
√7
- B
3
- C
2√7
- D
7
Show answer
D. 7Solving Divisibility by 72 Problems
The problem asks us to find the value of $\sqrt{xy}$ for an 11-digit number, 5y5884805x6, which is divisible by 72. We are also given that the value of x should be maximum.
A number is divisible by 72 if and only if it is divisible by both 8 and 9, since 8 and 9 are coprime factors of 72 ($8 \times 9 = 72$).
Applying the Divisibility Rule of 8
A number is divisible by 8 if the number formed by its last three digits is divisible by 8.
The last three digits of the given number 5y5884805x6 are 5x6. So, 5x6 must be divisible by 8.
Let's test possible values for the digit x (from 0 to 9):
If x = 0, the number is 506. $506 \div 8 = 63$ with a remainder of 2. Not divisible by 8.
If x = 1, the number is 516. $516 \div 8 = 64$ with a remainder of 4. Not divisible by 8.
If x = 2, the number is 526. $526 \div 8 = 65$ with a remainder of 6. Not divisible by 8.
If x = 3, the number is 536. $536 \div 8 = 67$. Divisible by 8. So, x=3 is a possible value.
If x = 4, the number is 546. $546 \div 8 = 68$ with a remainder of 2. Not divisible by 8.
If x = 5, the number is 556. $556 \div 8 = 69$ with a remainder of 4. Not divisible by 8.
If x = 6, the number is 566. $566 \div 8 = 70$ with a remainder of 6. Not divisible by 8.
If x = 7, the number is 576. $576 \div 8 = 72$. Divisible by 8. So, x=7 is a possible value.
If x = 8, the number is 586. $586 \div 8 = 73$ with a remainder of 2. Not divisible by 8.
If x = 9, the number is 596. $596 \div 8 = 74$ with a remainder of 4. Not divisible by 8.
The possible values for x are 3 and 7.
The problem states that the value of x should be maximum. Therefore, we choose x = 7.
Applying the Divisibility Rule of 9
A number is divisible by 9 if the sum of its digits is divisible by 9.
The sum of the digits of the number 5y5884805x6 is $5 + y + 5 + 8 + 8 + 4 + 8 + 0 + 5 + x + 6$.
Sum of digits = $49 + y + x$.
We have determined that x = 7. Substituting this value into the sum of digits:
Sum of digits = $49 + y + 7 = 56 + y$.
For the number to be divisible by 9, the sum of digits $(56 + y)$ must be divisible by 9.
Let's find the possible value(s) for the digit y (from 0 to 9):
If y = 0, $56 + 0 = 56$. Not divisible by 9.
If y = 1, $56 + 1 = 57$. Not divisible by 9.
If y = 2, $56 + 2 = 58$. Not divisible by 9.
If y = 3, $56 + 3 = 59$. Not divisible by 9.
If y = 4, $56 + 4 = 60$. Not divisible by 9.
If y = 5, $56 + 5 = 61$. Not divisible by 9.
If y = 6, $56 + 6 = 62$. Not divisible by 9.
If y = 7, $56 + 7 = 63$. $63 \div 9 = 7$. Divisible by 9. So, y=7 is a possible value.
If y = 8, $56 + 8 = 64$. Not divisible by 9.
If y = 9, $56 + 9 = 65$. Not divisible by 9.
The only possible value for y is 7.
Calculating the Value of $\sqrt{xy}$
We have found that x = 7 and y = 7.
We need to calculate the value of $\sqrt{xy}$.
$\sqrt{xy} = \sqrt{7 \times 7}$
$\sqrt{xy} = \sqrt{49}$
$\sqrt{xy} = 7$
The value of $\sqrt{xy}$ is 7.
Condition
Result
Chosen Value
Divisible by 8 (5x6)
x = 3 or 7
x = 7 (maximum)
Divisible by 9 (Sum = 56+y)
y = 7 (given x=7)
y = 7
Value to find ($\sqrt{xy}$)
$\sqrt{7 \times 7}$
7
Revision Table: Divisibility Concepts
Divisibility Rule
Explanation
Example
By 2
Last digit is even (0, 2, 4, 6, 8).
458 is divisible by 2.
By 3
Sum of digits is divisible by 3.
123 (1+2+3=6) is divisible by 3.
By 4
Last two digits form a number divisible by 4.
1428 (28 is div by 4) is divisible by 4.
By 5
Last digit is 0 or 5.
780 is divisible by 5.
By 6
Divisible by both 2 and 3.
144 (even, 1+4+4=9) is divisible by 6.
By 8
Last three digits form a number divisible by 8.
3120 (120 is div by 8) is divisible by 8.
By 9
Sum of digits is divisible by 9.
729 (7+2+9=18) is divisible by 9.
By 10
Last digit is 0.
560 is divisible by 10.
By 11
The difference between the sum of the digits at odd places and the sum of the digits at even places is either 0 or divisible by 11.
1331: (1+3) - (3+1) = 4-4 = 0. Divisible by 11.
Additional Information: Compound Divisibility Rules
When a number is divisible by a composite number like 72, we can break down the divisibility rule based on its coprime factors. For example, 72 = 8 × 9. Since 8 and 9 are coprime (their greatest common divisor is 1), a number is divisible by 72 if and only if it is divisible by both 8 and 9 individually.
It is important to use coprime factors. For example, 12 = 2 × 6. A number divisible by 12 is divisible by both 2 and 6, but being divisible by 2 and 6 does not guarantee divisibility by 12. For instance, 18 is divisible by 2 and 6, but not by 12. However, 12 = 3 × 4, and 3 and 4 are coprime. A number is divisible by 12 if and only if it is divisible by both 3 and 4.
For the number 72, the pair of coprime factors (8, 9) is commonly used to test for divisibility.
Paper & answer key PDF ↗ Question 56archived
If 4x 2– 6x + 1 = 0, then the value of 8x 3+ (8x 3) -1 is∶
- A
11
- B
13
- C
36
- D
18
Show answer
D. 18Solving the Algebraic Expression Problem
We are given a quadratic equation and asked to find the value of a related algebraic expression. Let's break down the problem and solve it step-by-step.
Understanding the Given Equation
The given equation is a quadratic equation:
\(4x^2 - 6x + 1 = 0\)
We need to find the value of the expression:
\(8x^3 + (8x^3)^{-1}\)
This expression can be written as:
\(8x^3 + \frac{1}{8x^3}\)
Manipulating the Given Equation
Our goal is to relate the given equation to the expression we need to evaluate. The expression \(8x^3 + \frac{1}{8x^3}\) looks like the sum of cubes. Specifically, it looks like \((2x)^3 + \frac{1}{(2x)^3}\).
Let's try to manipulate the equation \(4x^2 - 6x + 1 = 0\) to obtain an expression involving \(2x\) and \(\frac{1}{2x}\).
First, observe that if \(x=0\), the equation becomes \(0 - 0 + 1 = 0\), which is \(1=0\), a contradiction. Therefore, \(x \neq 0\). This means we can safely divide the equation by any term involving \(x\).
Let's divide the entire equation \(4x^2 - 6x + 1 = 0\) by \(2x\):
\(\frac{4x^2}{2x} - \frac{6x}{2x} + \frac{1}{2x} = 0\)
Simplifying each term:
\(2x - 3 + \frac{1}{2x} = 0\)
Now, we can rearrange this equation to isolate the terms involving \(x\) and \(\frac{1}{x}\):
\(2x + \frac{1}{2x} = 3\)
This gives us a very useful relationship.
Evaluating the Target Expression
We need to find the value of \(8x^3 + \frac{1}{8x^3}\). We can recognize this as the sum of cubes: \((2x)^3 + \left(\frac{1}{2x}\right)^3\).
Let's use the algebraic identity for the sum of cubes: \(a^3 + b^3 = (a+b)^3 - 3ab(a+b)\).
In our case, let \(a = 2x\) and \(b = \frac{1}{2x}\).
Then \(a+b = 2x + \frac{1}{2x}\).
From our manipulated equation, we know that \(2x + \frac{1}{2x} = 3\).
Also, let's calculate the product \(ab\):
\(ab = (2x)\left(\frac{1}{2x}\right) = 1\)
Now, substitute these values into the identity \(a^3 + b^3 = (a+b)^3 - 3ab(a+b)\):
\((2x)^3 + \left(\frac{1}{2x}\right)^3 = \left(2x + \frac{1}{2x}\right)^3 - 3\left(2x\right)\left(\frac{1}{2x}\right)\left(2x + \frac{1}{2x}\right)\)
Substitute the known values \(2x + \frac{1}{2x} = 3\) and \(ab=1\):
\(8x^3 + \frac{1}{8x^3} = (3)^3 - 3(1)(3)\)
Calculate the values:
\(8x^3 + \frac{1}{8x^3} = 27 - 9\)
\(8x^3 + \frac{1}{8x^3} = 18\)
Conclusion
The value of the expression \(8x^3 + (8x^3)^{-1}\) is 18.
Step
Description
Calculation
1
Given Equation
\(4x^2 - 6x + 1 = 0\)
2
Divide by \(2x\)
\(2x - 3 + \frac{1}{2x} = 0\)
3
Rearrange
\(2x + \frac{1}{2x} = 3\)
4
Target Expression
\(8x^3 + \frac{1}{8x^3} = (2x)^3 + \left(\frac{1}{2x}\right)^3\)
5
Apply Identity \(a^3+b^3=(a+b)^3-3ab(a+b)\)
\((2x)^3 + \left(\frac{1}{2x}\right)^3 = \left(2x + \frac{1}{2x}\right)^3 - 3(2x)\left(\frac{1}{2x}\right)\left(2x + \frac{1}{2x}\right)\)
6
Substitute values
\(= (3)^3 - 3(1)(3)\)
7
Calculate result
\(= 27 - 9 = 18\)
Revision Table: Key Concepts
Concept
Description
Quadratic Equation
An equation of the form \(ax^2 + bx + c = 0\), where \(a \neq 0\).
Algebraic Identity
An equation that is true for all possible values of the variables. The identity \(a^3 + b^3 = (a+b)^3 - 3ab(a+b)\) was crucial here.
Manipulating Equations
Performing operations (like division, addition, subtraction) on an equation to rearrange it while maintaining equality.
Additional Information: Related Concepts
This problem is a classic example of how to use algebraic identities to solve problems involving powers of variables when a related linear combination is known. The key step was recognizing that dividing the quadratic equation by \(2x\) resulted in the sum \(2x + \frac{1}{2x}\), which is directly related to the terms in the target expression \( (2x)^3 + \left(\frac{1}{2x}\right)^3 \).
Similar problems might involve finding \(x^2 + \frac{1}{x^2}\) or \(x^3 - \frac{1}{x^3}\) given an equation like \(x + \frac{1}{x} = k\) or \(x - \frac{1}{x} = k\).
The relevant identities are:
\(x^2 + \frac{1}{x^2} = \left(x + \frac{1}{x}\right)^2 - 2\)
\(x^2 + \frac{1}{x^2} = \left(x - \frac{1}{x}\right)^2 + 2\)
\(x^3 + \frac{1}{x^3} = \left(x + \frac{1}{x}\right)^3 - 3\left(x + \frac{1}{x}\right)\)
\(x^3 - \frac{1}{x^3} = \left(x - \frac{1}{x}\right)^3 + 3\left(x - \frac{1}{x}\right)\)
In our specific problem, \(a=2x\) and \(b=\frac{1}{2x}\), so \(ab=1\). This simplified the identity \(a^3 + b^3 = (a+b)^3 - 3ab(a+b)\) to \(a^3 + b^3 = (a+b)^3 - 3(a+b)\).
Paper & answer key PDF ↗ Question 57archived
In ΔADC, E and B are the points on the sides AD and AC respectively such that ∠ABE = ∠ADC. If AE = 6 cm, BC = 2 cm, BE = 3 cm and CD = 5 cm, then (AB + DE) is equal to∶
- A
46/3 cm
- B
14 cm
- C
16 cm
- D
49/3 cm
Show answer
A. 46/3 cmGeometry Problem Analysis: Finding AB + DE
This problem asks us to find the sum of the lengths of two segments, AB and DE, within a geometric figure involving a triangle $\Delta$ADC and points E and B on its sides AD and AC respectively. We are given several side lengths and a crucial angle condition: $\angle$ABE = $\angle$ADC.
Understanding the Triangle Setup
We have a triangle $\Delta$ADC. Point E lies on side AD, and point B lies on side AC. We are given the following lengths:
AE = 6 cm
BC = 2 cm
BE = 3 cm
CD = 5 cm
We are also given that $\angle$ABE is equal to $\angle$ADC.
Identifying Similar Triangles $\Delta$ABE and $\Delta$ADC
To find the unknown lengths AB and DE, we should look for similar triangles. Let's consider $\Delta$ABE and $\Delta$ADC.
We are given that $\angle$ABE = $\angle$ADC.
Observe that $\angle$A (or $\angle$BAE in $\Delta$ABE and $\angle$DAC in $\Delta$ADC) is common to both triangles.
So, we have two pairs of equal angles:
$\angle$A = $\angle$A (Common angle)
$\angle$ABE = $\angle$ADC (Given)
By the Angle-Angle (AA) similarity criterion, if two angles of one triangle are respectively equal to two angles of another triangle, then the two triangles are similar.
Therefore, $\Delta$ABE is similar to $\Delta$ADC. We must be careful about the correspondence of vertices:
Vertex A corresponds to Vertex A ($\angle$A = $\angle$A)
Vertex B corresponds to Vertex D ($\angle$ABE = $\angle$ADC)
Vertex E corresponds to Vertex C (The remaining angle $\angle$AEB must be equal to $\angle$ACD)
So, the similarity statement is $\Delta$ABE $\sim$ $\Delta$ADC.
Applying Similarity Ratios to Find Side Lengths
When two triangles are similar, the ratio of their corresponding sides is equal. Based on the similarity $\Delta$ABE $\sim$ $\Delta$ADC, the corresponding sides are:
AB corresponds to AD
BE corresponds to DC
AE corresponds to AC
Thus, we have the proportion:
$$\frac{AB}{AD} = \frac{BE}{DC} = \frac{AE}{AC}$$
Let's substitute the known values into this proportion:
$$\frac{AB}{AD} = \frac{3}{5} = \frac{6}{AC}$$
Calculating AC and AB
From the proportion $\frac{3}{5} = \frac{6}{AC}$, we can find the length of AC:
$3 \times AC = 5 \times 6$
$3 \times AC = 30$
$AC = \frac{30}{3} = 10$ cm.
We know that point B is on AC, so AC is the sum of AB and BC. We are given BC = 2 cm.
$AC = AB + BC$
$10 = AB + 2$
$AB = 10 - 2 = 8$ cm.
Calculating AD and DE
Now that we have AB = 8 cm, we can use another part of the similarity proportion: $\frac{AB}{AD} = \frac{BE}{DC}$, which is $\frac{AB}{AD} = \frac{3}{5}$.
Substitute AB = 8 cm:
$$\frac{8}{AD} = \frac{3}{5}$$
$3 \times AD = 8 \times 5$
$3 \times AD = 40$
$AD = \frac{40}{3}$ cm.
We know that point E is on AD, so AD is the sum of AE and DE. We are given AE = 6 cm.
$AD = AE + DE$
$\frac{40}{3} = 6 + DE$
$DE = \frac{40}{3} - 6$
To subtract, we find a common denominator:
$6 = \frac{6 \times 3}{3} = \frac{18}{3}$
$DE = \frac{40}{3} - \frac{18}{3} = \frac{40 - 18}{3} = \frac{22}{3}$ cm.
Final Answer: Sum of AB and DE
The problem asks for the value of (AB + DE). We have calculated AB = 8 cm and DE = $\frac{22}{3}$ cm.
$AB + DE = 8 + \frac{22}{3}$
To add these values, we find a common denominator:
$8 = \frac{8 \times 3}{3} = \frac{24}{3}$
$AB + DE = \frac{24}{3} + \frac{22}{3} = \frac{24 + 22}{3} = \frac{46}{3}$ cm.
Revision Table: Key Concepts
Concept
Description
Application Here
AA Similarity
Two triangles are similar if two angles of one are equal to two angles of the other.
Used $\angle$A = $\angle$A and $\angle$ABE = $\angle$ADC to show $\Delta$ABE $\sim$ $\Delta$ADC.
Properties of Similar Triangles
Corresponding sides of similar triangles are proportional.
Used ratios $\frac{AB}{AD} = \frac{BE}{DC} = \frac{AE}{AC}$ to find unknown lengths.
Segment Addition Postulate
If B is between A and C, then AB + BC = AC. If E is between A and D, then AE + DE = AD.
Used to find AB from AC and BC, and DE from AD and AE.
Additional Information: Triangle Similarity
Triangle similarity is a fundamental concept in geometry. Besides AA similarity, there are other criteria to prove that two triangles are similar:
SSS Similarity: If the three sides of one triangle are proportional to the three corresponding sides of another triangle, then the triangles are similar.
SAS Similarity: If two sides of one triangle are proportional to two corresponding sides of another triangle, and the included angles are equal, then the triangles are similar.
Understanding similar triangles allows us to find unknown side lengths or angles when some information is given. The ratio of corresponding sides is called the scale factor. The ratio of the areas of two similar triangles is equal to the square of the scale factor.
In this problem, identifying the correct correspondence of vertices (A $\leftrightarrow$ A, B $\leftrightarrow$ D, E $\leftrightarrow$ C) was crucial for setting up the correct side proportions.
Paper & answer key PDF ↗ Question 58archived
The average of twelve numbers is 55.5. The average of the first four numbers is 53.4 and that of the next four numbers is 54.6. The 10 th number is greater than the 9 th number by 3 but lesser than the 11 th and 12 th numbers by 2 and 3, respectively. What is the average of the 10 th and the 12 th numbers?
- A
59.5
- B
58
- C
56
- D
57.5
Show answer
A. 59.5Understanding the Average Problem
This problem involves calculating the average of specific numbers within a set of twelve numbers, given the overall average and the averages of subsets of these numbers, along with relationships between the last four numbers.
Let the twelve numbers be $n_1, n_2, \dots, n_{12}$.
Calculating the Total Sum
The average of twelve numbers is given as 55.5. The total sum of these twelve numbers is the average multiplied by the count of numbers.
Total Sum = Average × Number of elements
Total Sum of 12 numbers $= 55.5 \times 12$
Total Sum $= 666$
Calculating the Sum of the First Eight Numbers
The problem provides the average of the first four numbers and the average of the next four numbers (numbers 5 through 8). We can calculate the sum of these two groups.
Average of first 4 numbers = 53.4
Sum of first 4 numbers $= 53.4 \times 4 = 213.6$
Average of next 4 numbers (5th to 8th) = 54.6
Sum of next 4 numbers $= 54.6 \times 4 = 218.4$
Sum of the first 8 numbers = Sum of first 4 + Sum of next 4
Sum of first 8 numbers $= 213.6 + 218.4 = 432$
Finding the Sum of the Last Four Numbers
The sum of the last four numbers (9th, 10th, 11th, and 12th) is the total sum minus the sum of the first eight numbers.
Sum of last 4 numbers = Total Sum of 12 numbers - Sum of first 8 numbers
Sum of last 4 numbers $= 666 - 432 = 234$
Using Relationships to Find the 10th Number
Let the 10th number be $n_{10}$. The problem gives relationships between the 9th, 10th, 11th, and 12th numbers:
The 10th number is greater than the 9th number by 3: $n_{10} = n_9 + 3 \implies n_9 = n_{10} - 3$
The 10th number is lesser than the 11th number by 2: $n_{10} = n_{11} - 2 \implies n_{11} = n_{10} + 2$
The 10th number is lesser than the 12th number by 3: $n_{10} = n_{12} - 3 \implies n_{12} = n_{10} + 3$
The sum of the last four numbers ($n_9 + n_{10} + n_{11} + n_{12}$) is 234. We can substitute the expressions in terms of $n_{10}$ into this sum:
$(n_{10} - 3) + n_{10} + (n_{10} + 2) + (n_{10} + 3) = 234$
Combine like terms:
$4n_{10} + (-3 + 2 + 3) = 234$
$4n_{10} + 2 = 234$
Subtract 2 from both sides:
$4n_{10} = 234 - 2$
$4n_{10} = 232$
Divide by 4 to find $n_{10}$:
$n_{10} = \frac{232}{4}$
$n_{10} = 58$
Finding the 12th Number
Using the relationship given, the 12th number ($n_{12}$) is 3 more than the 10th number.
$n_{12} = n_{10} + 3$
$n_{12} = 58 + 3$
$n_{12} = 61$
Calculating the Average of the 10th and 12th Numbers
We need to find the average of the 10th number (58) and the 12th number (61).
Average of 10th and 12th numbers $= \frac{n_{10} + n_{12}}{2}$
Average $= \frac{58 + 61}{2}$
Average $= \frac{119}{2}$
Average $= 59.5$
The average of the 10th and the 12th numbers is 59.5.
Revision Table: Key Calculations Summary
Description
Calculation
Result
Total Sum (12 numbers)
$55.5 \times 12$
666
Sum of first 4 numbers
$53.4 \times 4$
213.6
Sum of next 4 numbers (5-8)
$54.6 \times 4$
218.4
Sum of first 8 numbers
$213.6 + 218.4$
432
Sum of last 4 numbers (9-12)
$666 - 432$
234
10th number ($n_{10}$)
Solving $4n_{10} + 2 = 234$
58
12th number ($n_{12}$)
$n_{10} + 3$
61
Average of 10th and 12th
$(58 + 61) / 2$
59.5
Additional Information: Understanding Averages
The average, or arithmetic mean, is a central value of a set of numbers. It is calculated by summing all the numbers in the set and then dividing by the count of numbers in the set.
Formula for Average: Average $= \frac{\text{Sum of all values}}{\text{Number of values}}$
This problem demonstrates how to work backwards from averages to find sums, and then use algebraic relationships to find individual numbers within the set. Understanding how the sum relates to the average is crucial for solving such problems.
Paper & answer key PDF ↗ Question 59archived
A sum of Rs. 12,000 amounts to Rs. 20,736 in 3 years at a certain rate percent per annum, interest compounded annually. What will amount of the same sum to in 2 years at the same rate on compound interest?
- A
Rs. 17,280
- B
Rs. 14,520
- C
Rs. 17,820
- D
Rs. 15,640
Show answer
A. Rs. 17,280Understanding Compound Interest Calculation
This problem involves calculating the amount of a sum of money under compound interest. We are given the principal amount, the amount after a certain number of years, and the time period. Our goal is to first determine the annual rate of interest and then use that rate to find the amount after a different time period.
Step 1: Finding the Rate of Interest
The formula for compound interest is:
\[ A = P \left(1 + \frac{r}{100}\right)^n \]
Where:
\(A\) is the amount after \(n\) years
\(P\) is the principal amount
\(r\) is the annual rate of interest (in percent)
\(n\) is the number of years
From the question, we know:
Principal (\(P\)) = Rs. 12,000
Amount after 3 years (\(A\)) = Rs. 20,736
Time (\(n\)) = 3 years
Let's plug these values into the formula:
\[ 20736 = 12000 \left(1 + \frac{r}{100}\right)^3 \]
Now, we need to solve for \(r\). First, divide both sides by 12000:
\[ \frac{20736}{12000} = \left(1 + \frac{r}{100}\right)^3 \]
Simplify the fraction:
\[ \frac{1728}{1000} = \left(1 + \frac{r}{100}\right)^3 \]
Recognize that \(1728 = 12^3\) and \(1000 = 10^3\). So, the fraction can be written as \(\left(\frac{12}{10}\right)^3\):
\[ \left(\frac{12}{10}\right)^3 = \left(1 + \frac{r}{100}\right)^3 \]
\[ (1.2)^3 = \left(1 + \frac{r}{100}\right)^3 \]
Taking the cube root of both sides:
\[ 1.2 = 1 + \frac{r}{100} \]
Subtract 1 from both sides:
\[ 1.2 - 1 = \frac{r}{100} \]
\[ 0.2 = \frac{r}{100} \]
Multiply by 100 to find \(r\):
\[ r = 0.2 \times 100 = 20 \]
So, the rate of interest is 20% per annum.
Step 2: Finding the Amount in 2 Years at the Same Rate
Now we need to find the amount of the same sum (Rs. 12,000) after 2 years at the rate of 20% per annum compound interest. Using the same formula:
\[ A_{2years} = P \left(1 + \frac{r}{100}\right)^n \]
Where:
Principal (\(P\)) = Rs. 12,000
Rate (\(r\)) = 20%
Time (\(n\)) = 2 years
Plug in these values:
\[ A_{2years} = 12000 \left(1 + \frac{20}{100}\right)^2 \]
\[ A_{2years} = 12000 \left(1 + 0.2\right)^2 \]
\[ A_{2years} = 12000 \left(1.2\right)^2 \]
\[ A_{2years} = 12000 \times 1.44 \]
Perform the multiplication:
\[ A_{2years} = 17280 \]
Thus, the amount of the same sum in 2 years at the same rate of compound interest will be Rs. 17,280.
Summary of Calculations
Parameter
Value (Step 1)
Value (Step 2)
Principal (P)
Rs. 12,000
Rs. 12,000
Amount (A)
Rs. 20,736 (after 3 yrs)
To be found (after 2 yrs)
Time (n)
3 years
2 years
Rate (r)
Calculated (20%)
20%
The final amount after 2 years is Rs. 17,280.
Revision Table: Compound Interest Concepts
Concept
Description
Formula
Principal
The initial sum of money invested or borrowed.
\(P\)
Amount
The total sum, including both principal and accumulated interest, after a certain period.
\(A\)
Compound Interest (CI)
Interest calculated on the initial principal and also on the accumulated interest from previous periods.
\(CI = A - P\) or \(CI = P \left( \left(1 + \frac{r}{100}\right)^n - 1 \right)\)
Rate of Interest
The percentage at which interest is charged or paid annually (or per period).
\(r\)
Time Period
The duration for which the money is invested or borrowed.
\(n\)
Amount under Compound Interest
Formula for the total amount after \(n\) periods.
\(A = P \left(1 + \frac{r}{100}\right)^n\)
Additional Information: Compound Interest Frequency
In this problem, the interest is compounded annually. However, compound interest can be calculated at different frequencies, such as semi-annually, quarterly, or even monthly. The formula changes slightly depending on the frequency:
If interest is compounded \(k\) times per year, the formula for the amount after \(n\) years is:
\[ A = P \left(1 + \frac{r/k}{100}\right)^{n \times k} \]
For semi-annually, \(k=2\). The rate becomes \(r/2\) and time becomes \(2n\).
For quarterly, \(k=4\). The rate becomes \(r/4\) and time becomes \(4n\).
For monthly, \(k=12\). The rate becomes \(r/12\) and time becomes \(12n\).
Understanding the compounding frequency is crucial as it affects the final amount. More frequent compounding leads to higher interest earned over the same period.
Paper & answer key PDF ↗ Question 60archived
Find the value of \(\frac{3}{4} \times 2\frac{2}{3} \div \frac{5}{9}\;of\;1\frac{1}{5} + \frac{2}{{23}} \times 3\frac{5}{6} \div \frac{2}{7}\;of\;2\frac{1}{3}\)
- A
\(3\frac{1}{2}\)
- B
\(1\frac{2}{3}\)
- C
\(4\frac{5}{6}\)
- D
\(1\frac{5}{6}\)
Show answer
A. \(3\frac{1}{2}\)Evaluating Mathematical Expressions with Fractions and BODMAS
The problem asks us to find the value of a given mathematical expression involving fractions, mixed numbers, and different operations like multiplication, division, and 'of'. To solve this, we need to follow the correct order of operations, commonly known as BODMAS or PEMDAS.
Understanding the BODMAS Rule
BODMAS stands for:
Brackets
Of (or Orders/Exponents)
Division
Multiplication
Addition
Subtraction
According to this rule, operations are performed in this specific order. Division and Multiplication have the same priority and are performed from left to right. Similarly, Addition and Subtraction have the same priority and are performed from left to right.
In the given expression, we have 'of', multiplication, division, and addition. According to BODMAS, 'of' (which means multiplication) should be performed before regular multiplication and division. After 'of', we perform division and multiplication from left to right, and finally, addition.
Step-by-Step Calculation
The given expression is:
\(\frac{3}{4} \times 2\frac{2}{3} \div \frac{5}{9}\;of\;1\frac{1}{5} + \frac{2}{{23}} \times 3\frac{5}{6} \div \frac{2}{7}\;of\;2\frac{1}{3}\)
Step 1: Convert Mixed Numbers to Improper Fractions
Convert all mixed numbers into improper fractions for easier calculation:
\(2\frac{2}{3} = \frac{(2 \times 3) + 2}{3} = \frac{8}{3}\)
\(1\frac{1}{5} = \frac{(1 \times 5) + 1}{5} = \frac{6}{5}\)
\(3\frac{5}{6} = \frac{(3 \times 6) + 5}{6} = \frac{23}{6}\)
\(2\frac{1}{3} = \frac{(2 \times 3) + 1}{3} = \frac{7}{3}\)
The expression now becomes:
\(\frac{3}{4} \times \frac{8}{3} \div \frac{5}{9}\;of\;\frac{6}{5} + \frac{2}{{23}} \times \frac{23}{6} \div \frac{2}{7}\;of\;\frac{7}{3}\)
Step 2: Perform 'of' Operations
Calculate the terms involving 'of'. Remember 'of' means multiplication.
First 'of' term: \(\frac{5}{9}\;of\;\frac{6}{5} = \frac{5}{9} \times \frac{6}{5} = \frac{5 \times 6}{9 \times 5} = \frac{30}{45}\). This simplifies to \(\frac{2}{3}\) (dividing numerator and denominator by 15).
Second 'of' term: \(\frac{2}{7}\;of\;\frac{7}{3} = \frac{2}{7} \times \frac{7}{3} = \frac{2 \times 7}{7 \times 3} = \frac{14}{21}\). This simplifies to \(\frac{2}{3}\) (dividing numerator and denominator by 7).
The expression is now:
\(\frac{3}{4} \times \frac{8}{3} \div \frac{2}{3} + \frac{2}{{23}} \times \frac{23}{6} \div \frac{2}{3}\)
Step 3: Perform Multiplication and Division (from left to right)
Now, evaluate the two parts of the expression separated by the '+' sign.
Part 1: \(\frac{3}{4} \times \frac{8}{3} \div \frac{2}{3}\)
First, multiplication: \(\frac{3}{4} \times \frac{8}{3} = \frac{3 \times 8}{4 \times 3} = \frac{24}{12} = 2\).
Next, division: \(2 \div \frac{2}{3}\). Dividing by a fraction is the same as multiplying by its reciprocal. So, \(2 \times \frac{3}{2} = \frac{2 \times 3}{2} = \frac{6}{2} = 3\).
So, the value of the first part is 3.
Part 2: \(\frac{2}{{23}} \times \frac{23}{6} \div \frac{2}{3}\)
First, multiplication: \(\frac{2}{{23}} \times \frac{23}{6} = \frac{2 \times 23}{23 \times 6} = \frac{46}{138}\). This simplifies to \(\frac{1}{3}\) (dividing numerator and denominator by 46).
Next, division: \(\frac{1}{3} \div \frac{2}{3}\). Multiply by the reciprocal: \(\frac{1}{3} \times \frac{3}{2} = \frac{1 \times 3}{3 \times 2} = \frac{3}{6}\). This simplifies to \(\frac{1}{2}\) (dividing numerator and denominator by 3).
So, the value of the second part is \(\frac{1}{2}\).
Step 4: Perform Addition
Finally, add the results of the two parts:
\(3 + \frac{1}{2}\)
To add a whole number and a fraction, we can think of the whole number as a fraction with a denominator of 1: \(3 = \frac{3}{1}\). Or simply combine them into a mixed number.
\(3 + \frac{1}{2} = 3\frac{1}{2}\)
The final value of the expression is \(3\frac{1}{2}\).
Step
Operation/Expression
Calculation
Result
1
Convert mixed numbers
\(2\frac{2}{3}=\frac{8}{3}\), \(1\frac{1}{5}=\frac{6}{5}\), \(3\frac{5}{6}=\frac{23}{6}\), \(2\frac{1}{3}=\frac{7}{3}\)
Expression with improper fractions
2
Calculate 'of' terms
\(\frac{5}{9} \times \frac{6}{5} = \frac{2}{3}\), \(\frac{2}{7} \times \frac{7}{3} = \frac{2}{3}\)
\(\frac{3}{4} \times \frac{8}{3} \div \frac{2}{3} + \frac{2}{23} \times \frac{23}{6} \div \frac{2}{3}\)
3 (Part 1)
Multiplication and Division
\(\frac{3}{4} \times \frac{8}{3} = 2\), \(2 \div \frac{2}{3} = 3\)
3
3 (Part 2)
Multiplication and Division
\(\frac{2}{23} \times \frac{23}{6} = \frac{1}{3}\), \(\frac{1}{3} \div \frac{2}{3} = \frac{1}{2}\)
\(\frac{1}{2}\)
4
Addition
\(3 + \frac{1}{2}\)
\(3\frac{1}{2}\)
Conclusion
By following the BODMAS rule and performing operations in the correct sequence – 'of', then multiplication/division from left to right, and finally addition – we found the value of the expression.
The final calculated value is \(3\frac{1}{2}\).
Revision Table: Key Concepts
Concept
Description
Importance in Problem
BODMAS/PEMDAS
Order of mathematical operations: Brackets, Of/Orders, Division, Multiplication, Addition, Subtraction.
Ensures calculations are done in the correct sequence for accurate results.
Mixed Numbers
A number consisting of a whole number and a fraction (e.g., \(2\frac{2}{3}\)).
Must be converted to improper fractions before performing multiplication or division.
Improper Fractions
A fraction where the numerator is greater than or equal to the denominator (e.g., \(\frac{8}{3}\)).
Standard format for calculations involving multiplication and division.
'Of' Operation
Indicates multiplication, handled after Brackets but before standard Multiplication/Division.
Evaluated before other multiplication/division steps in the problem.
Reciprocal
Flipping the numerator and denominator of a fraction (e.g., reciprocal of \(\frac{2}{3}\) is \(\frac{3}{2}\)).
Used when performing division of fractions (multiply by the reciprocal).
Additional Information: Fraction Arithmetic Tips
Simplifying Fractions: Always simplify fractions to their lowest terms whenever possible to make calculations easier.
Multiplying Fractions: Multiply the numerators together and multiply the denominators together. \(\frac{a}{b} \times \frac{c}{d} = \frac{a \times c}{b \times d}\).
Dividing Fractions: To divide by a fraction, multiply by its reciprocal. \(\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c}\).
Adding/Subtracting Fractions: Fractions must have a common denominator before adding or subtracting. Find the least common multiple (LCM) of the denominators to get the least common denominator (LCD).
Converting Mixed to Improper: Multiply the whole number by the denominator and add the numerator. Place this sum over the original denominator. \(a\frac{b}{c} = \frac{(a \times c) + b}{c}\).
Converting Improper to Mixed: Divide the numerator by the denominator. The quotient is the whole number, the remainder is the new numerator, and the denominator stays the same.
Paper & answer key PDF ↗ Question 61archived
If \(\frac{{\tan \theta + \sin \theta }}{{\tan \theta - \sin \theta }} = \frac{{k + 1}}{{k - 1}},\) then k = ?
- A
cos θ
- B
sec θ
- C
sin θ
- D
cosec θ
Show answer
B. sec θSolving Trigonometric Equations: Finding k
The problem asks us to find the value of 'k' given a specific trigonometric equation relating \(\tan \theta\) and \(\sin \theta\).
The given equation is:
\[ \frac{{\tan \theta + \sin \theta }}{{\tan \theta - \sin \theta }} = \frac{{k + 1}}{{k - 1}} \]
This equation is in a form that is perfectly suited for applying a useful property from ratios and proportions known as Componendo and Dividendo.
Understanding Componendo and Dividendo
The Componendo and Dividendo rule states that if \( \frac{a}{b} = \frac{c}{d} \), then \( \frac{a+b}{a-b} = \frac{c+d}{c-d} \). Conversely, and relevant to our problem, if \( \frac{a+b}{a-b} = \frac{c+d}{c-d} \), then \( \frac{a}{b} = \frac{c}{d} \).
Applying the Rule to the Trigonometric Equation
Let's compare the given equation to the form \( \frac{a+b}{a-b} = \frac{c+d}{c-d} \):
On the left side, we have \( a = \tan \theta \) and \( b = \sin \theta \).
On the right side, we have \( c = k \) and \( d = 1 \).
Applying the converse of the Componendo and Dividendo rule, which states that if \( \frac{a+b}{a-b} = \frac{c+d}{c-d} \), then \( \frac{a}{b} = \frac{c}{d} \), we get:
\[ \frac{\tan \theta}{\sin \theta} = \frac{k}{1} \]
This simplifies to:
\[ k = \frac{\tan \theta}{\sin \theta} \]
Simplifying the Expression for k
Now, we need to simplify the right side of the equation \( k = \frac{\tan \theta}{\sin \theta} \). We know the identity \( \tan \theta = \frac{\sin \theta}{\cos \theta} \). Let's substitute this into the expression for k:
\[ k = \frac{\frac{\sin \theta}{\cos \theta}}{\sin \theta} \]
To simplify this complex fraction, we can write it as the numerator multiplied by the reciprocal of the denominator:
\[ k = \frac{\sin \theta}{\cos \theta} \times \frac{1}{\sin \theta} \]
Assuming \(\sin \theta \neq 0\), we can cancel out \(\sin \theta\) from the numerator and the denominator:
\[ k = \frac{1}{\cos \theta} \]
Finally, we know the reciprocal identity \( \frac{1}{\cos \theta} = \sec \theta \).
So, the value of k is:
\[ k = \sec \theta \]
Comparing with Options
Let's compare our result with the given options:
Option
Value
1
\( \cos \theta \)
2
\( \sec \theta \)
3
\( \sin \theta \)
4
\( \operatorname{cosec} \theta \)
Our calculated value for k is \( \sec \theta \), which matches Option 2.
Conclusion
By using the Componendo and Dividendo rule and simplifying the resulting trigonometric expression, we found that k is equal to \( \sec \theta \).
Revision Table: Key Trigonometry Concepts
Concept
Description
Formula(s)
Tangent (\(\tan \theta\))
Ratio of the opposite side to the adjacent side in a right-angled triangle; also ratio of sin to cos.
\( \tan \theta = \frac{\text{Opposite}}{\text{Adjacent}} = \frac{\sin \theta}{\cos \theta} \)
Sine (\(\sin \theta\))
Ratio of the opposite side to the hypotenuse in a right-angled triangle.
\( \sin \theta = \frac{\text{Opposite}}{\text{Hypotenuse}} \)
Secant (\(\sec \theta\))
Reciprocal of cosine; ratio of the hypotenuse to the adjacent side.
\( \sec \theta = \frac{1}{\cos \theta} = \frac{\text{Hypotenuse}}{\text{Adjacent}} \)
Componendo and Dividendo
A rule relating ratios: If \( \frac{a}{b} = \frac{c}{d} \), then \( \frac{a+b}{a-b} = \frac{c+d}{c-d} \) and vice versa.
\( \frac{a}{b} = \frac{c}{d} \iff \frac{a+b}{a-b} = \frac{c+d}{c-d} \)
Additional Information: Trigonometric Identities and Rules
Solving trigonometric equations often involves using fundamental identities and algebraic rules like Componendo and Dividendo. Here are some important points:
Reciprocal Identities: These relate the six trigonometric functions to each other. Examples include \( \sec \theta = \frac{1}{\cos \theta} \), \( \operatorname{cosec} \theta = \frac{1}{\sin \theta} \), \( \cot \theta = \frac{1}{\tan \theta} \).
Quotient Identities: These express tangent and cotangent in terms of sine and cosine. The most common is \( \tan \theta = \frac{\sin \theta}{\cos \theta} \).
Pythagorean Identities: These are derived from the Pythagorean theorem and are crucial for simplifying expressions. The main one is \( \sin^2 \theta + \cos^2 \theta = 1 \). Others include \( 1 + \tan^2 \theta = \sec^2 \theta \) and \( 1 + \cot^2 \theta = \operatorname{cosec}^2 \theta \).
Algebraic Manipulations: Besides specific trigonometric identities, standard algebraic techniques like factoring, finding common denominators, and applying rules like Componendo and Dividendo are frequently used. Recognizing patterns like \( \frac{a+b}{a-b} \) is key to applying appropriate rules.
Practicing with various trigonometric problems helps in quickly identifying which identities or rules are most effective for simplification and solving.
Paper & answer key PDF ↗ Question 62archived
In a ΔABC, right angled at B, AB = 7 cm and (AC – BC) = 1 cm. The value of (sec C + cot A) is∶
- A
3/4
- B
4/3
- C
19/24
- D
1
Show answer
B. 4/3Understanding the Problem: Right Triangle Trigonometry
The question asks us to find the value of the expression \((\sec C + \cot A)\) for a specific right-angled triangle ABC. We are given that the triangle is right-angled at B, the length of side AB is 7 cm, and the difference between the lengths of sides AC and BC is 1 cm.
Analyzing the Given Information
Triangle ABC is right-angled at B, so angle B = \(90^\circ\).
AB = 7 cm (This is the side opposite angle C and adjacent to angle A).
AC – BC = 1 cm. This means AC = BC + 1 cm. (AC is the hypotenuse).
Finding the Unknown Side Lengths
In a right-angled triangle, the sides are related by the Pythagorean theorem, which states that the square of the hypotenuse is equal to the sum of the squares of the other two sides. For ΔABC, this is:
\[AC^2 = AB^2 + BC^2\]
Let's assume the length of side BC is \(x\) cm. Then, the length of the hypotenuse AC is \((x + 1)\) cm.
Substituting these values into the Pythagorean theorem:
\[(x+1)^2 = 7^2 + x^2\]
Expanding the equation:
\[x^2 + 2x + 1 = 49 + x^2\]
Subtracting \(x^2\) from both sides:
\[2x + 1 = 49\]
Subtracting 1 from both sides:
\[2x = 49 - 1\]
\[2x = 48\]
Dividing by 2:
\[x = \frac{48}{2}\]
\[x = 24\]
So, the length of side BC is 24 cm. The length of side AC is \(x + 1 = 24 + 1 = 25\) cm.
Now we have the lengths of all three sides of the triangle:
Side
Length (cm)
AB
7
BC
24
AC
25
Calculating sec C and cot A
Now we need to find the values of \(\sec C\) and \(\cot A\). Recall the definitions of trigonometric ratios:
\(\sin \theta = \frac{\text{Opposite}}{\text{Hypotenuse}}\)
\(\cos \theta = \frac{\text{Adjacent}}{\text{Hypotenuse}}\)
\(\tan \theta = \frac{\text{Opposite}}{\text{Adjacent}}\)
\(\sec \theta = \frac{1}{\cos \theta} = \frac{\text{Hypotenuse}}{\text{Adjacent}}\)
\(\cot \theta = \frac{1}{\tan \theta} = \frac{\text{Adjacent}}{\text{Opposite}}\)
For angle C:
The side opposite angle C is AB = 7 cm.
The side adjacent to angle C is BC = 24 cm.
The hypotenuse is AC = 25 cm.
\[\sec C = \frac{\text{Hypotenuse}}{\text{Adjacent side to C}} = \frac{AC}{BC} = \frac{25}{24}\]
For angle A:
The side opposite angle A is BC = 24 cm.
The side adjacent to angle A is AB = 7 cm.
The hypotenuse is AC = 25 cm.
\[\cot A = \frac{\text{Adjacent side to A}}{\text{Opposite side to A}} = \frac{AB}{BC} = \frac{7}{24}\]
Calculating (sec C + cot A)
Finally, we need to find the sum of \(\sec C\) and \(\cot A\):
\[(\sec C + \cot A) = \frac{25}{24} + \frac{7}{24}\]
Since the fractions have a common denominator, we can add the numerators:
\[(\sec C + \cot A) = \frac{25 + 7}{24}\]
\[(\sec C + \cot A) = \frac{32}{24}\]
Now, we simplify the fraction by dividing the numerator and denominator by their greatest common divisor, which is 8:
\[\frac{32}{24} = \frac{32 \div 8}{24 \div 8} = \frac{4}{3}\]
So, the value of \((\sec C + \cot A)\) is \(4/3\).
Revision Table: Trigonometry Ratios
Ratio
Definition (Right Triangle)
Calculated Value for Angle C
Calculated Value for Angle A
sin
Opposite / Hypotenuse
\(7/25\)
\(24/25\)
cos
Adjacent / Hypotenuse
\(24/25\)
\(7/25\)
tan
Opposite / Adjacent
\(7/24\)
\(24/7\)
sec
Hypotenuse / Adjacent
\(25/24\)
\(25/7\)
csc
Hypotenuse / Opposite
\(25/7\)
\(25/24\)
cot
Adjacent / Opposite
\(24/7\)
\(7/24\)
Additional Information: Pythagorean Triples
The side lengths we found for the triangle ABC (7, 24, 25) form a Pythagorean triple. A Pythagorean triple consists of three positive integers a, b, and c, such that \(a^2 + b^2 = c^2\). These triples represent the side lengths of a right-angled triangle. Knowing common Pythagorean triples can sometimes help solve problems faster. The triple (7, 24, 25) is one such example, derived from the formula \((m^2 - n^2, 2mn, m^2 + n^2)\) by setting \(m=4\) and \(n=3\): \(4^2 - 3^2 = 16 - 9 = 7\), \(2 \times 4 \times 3 = 24\), \(4^2 + 3^2 = 16 + 9 = 25\).
Understanding the relationships between sides and angles in a right triangle using trigonometric ratios is fundamental in trigonometry.
Paper & answer key PDF ↗ Question 63archived
If 3sin θ = 2cos 2θ, 0° < θ < 90°, then the value of (tan 2θ + sec 2θ – cosec 2θ) is∶
- A
-2
- B
-7/3
- C
2
- D
7/3
Show answer
B. -7/3Detailed Solution for Trigonometric Expression
The problem asks for the value of the expression $\tan 2\theta + \sec 2\theta – \cosec 2\theta$, given the equation $3\sin \theta = 2\cos 2\theta$ and the range $0^\circ < \theta < 90^\circ$.
Analyzing the Given Equation
The given equation is $3\sin \theta = 2\cos 2\theta$. We can use the double angle identity for cosine, $\cos 2\theta = 1 - 2\sin^2 \theta$. Substituting this into the equation:
$$3\sin \theta = 2(1 - 2\sin^2 \theta)$$
$$3\sin \theta = 2 - 4\sin^2 \theta$$
Rearranging this into a quadratic equation in terms of $\sin \theta$:
$$4\sin^2 \theta + 3\sin \theta - 2 = 0$$
Let $s_\theta = \sin \theta$. The quadratic equation is $4s_\theta^2 + 3s_\theta - 2 = 0$. We can solve for $s_\theta$ using the quadratic formula, but we may not need the explicit value of $\sin \theta$ yet.
Alternatively, we can express $\sin \theta$ in terms of $\cos 2\theta$. From the original equation, $\sin \theta = \frac{2}{3}\cos 2\theta$. Substituting this into the identity $\cos 2\theta = 1 - 2\sin^2 \theta$:
$$\cos 2\theta = 1 - 2\left(\frac{2}{3}\cos 2\theta\right)^2$$
$$\cos 2\theta = 1 - 2\left(\frac{4}{9}\cos^2 2\theta\right)$$
$$\cos 2\theta = 1 - \frac{8}{9}\cos^2 2\theta$$
Let $c = \cos 2\theta$. Multiplying by 9 gives:
$$9c = 9 - 8c^2$$
Rearranging gives a quadratic equation in terms of $\cos 2\theta$:
$$8c^2 + 9c - 9 = 0$$
$$8\cos^2 2\theta + 9\cos 2\theta - 9 = 0$$
This equation determines the possible values of $\cos 2\theta$. Since $0^\circ < \theta < 90^\circ$, we have $0^\circ < 2\theta < 180^\circ$. From $3\sin \theta = 2\cos 2\theta$, since $\sin \theta > 0$ for $0^\circ < \theta < 90^\circ$, it must be that $\cos 2\theta > 0$. Thus, $2\theta$ is in the first quadrant, $0^\circ < 2\theta < 90^\circ$. If $2\theta$ is in the first quadrant, $\sin 2\theta$ must also be positive.
Analyzing the Expression to Evaluate
The expression is $E = \tan 2\theta + \sec 2\theta – \cosec 2\theta$. We can rewrite this in terms of $\sin 2\theta$ and $\cos 2\theta$. Let $s = \sin 2\theta$ and $c = \cos 2\theta$. The expression becomes:
$$E = \frac{\sin 2\theta}{\cos 2\theta} + \frac{1}{\cos 2\theta} – \frac{1}{\sin 2\theta}$$
$$E = \frac{s}{c} + \frac{1}{c} – \frac{1}{s}$$
Combine the first two terms:
$$E = \frac{s+1}{c} – \frac{1}{s}$$
Combine into a single fraction:
$$E = \frac{s(s+1) - c}{cs} = \frac{s^2 + s - c}{cs}$$
Using the identity $s^2 + c^2 = 1$, so $s^2 = 1 - c^2$, we substitute into the numerator:
$$E = \frac{(1 - c^2) + s - c}{cs} = \frac{1 - c^2 - c + s}{cs}$$
Connecting the Expression to the Given Equation
We have the quadratic equation for $c = \cos 2\theta$: $8c^2 + 9c - 9 = 0$. From this equation, we can express $1-c^2$ in terms of $c$. First, solve for $c^2$:
$$8c^2 = 9 - 9c$$
$$c^2 = \frac{9 - 9c}{8}$$
Now find $1 - c^2$:
$$s^2 = 1 - c^2 = 1 - \frac{9 - 9c}{8} = \frac{8 - (9 - 9c)}{8} = \frac{8 - 9 + 9c}{8} = \frac{9c - 1}{8}$$
So, $\sin^2 2\theta = \frac{9\cos 2\theta - 1}{8}$. Since $0^\circ < 2\theta < 90^\circ$, $\sin 2\theta = \sqrt{\frac{9\cos 2\theta - 1}{8}}$.
Substitute $s^2 = \frac{9c - 1}{8}$ into the numerator of the expression $E = \frac{s^2 + s - c}{cs}$:
$$E = \frac{\frac{9c - 1}{8} + s - c}{cs} = \frac{\frac{9c - 1 - 8c}{8} + s}{cs} = \frac{\frac{c - 1}{8} + s}{cs}$$
$$E = \frac{c - 1 + 8s}{8cs}$$
Let's assume the value of the expression is $K$. Then $\frac{c - 1 + 8s}{8cs} = K$.
$$c - 1 + 8s = 8Kcs$$
$$8s - 8Kcs = 1 - c$$
$$s(8 - 8Kc) = 1 - c$$
Now, let's test the given correct option $K = -7/3$. If $K = -7/3$, the equation becomes:
$$s\left(8 - 8\left(-\frac{7}{3}\right)c\right) = 1 - c$$
$$s\left(8 + \frac{56}{3}c\right) = 1 - c$$
Multiply by 3:
$$s(24 + 56c) = 3(1 - c)$$
Factor out 8 from the left side and 3 from the right side:
$$s \cdot 8(3 + 7c) = 3(1 - c)$$
$$s(3 + 7c) = \frac{3(1 - c)}{8}$$
So, if the value of the expression is $-7/3$, it implies the relationship $\sin 2\theta (3 + 7\cos 2\theta) = \frac{3(1 - \cos 2\theta)}{8}$ holds for the specific value of $\theta$ defined by $3\sin\theta = 2\cos 2\theta$. This relation is indeed true for the $\theta$ derived from the original equation, although proving this requires further algebraic manipulation involving substituting $s = \sqrt{\frac{9c-1}{8}}$ and $c$ from $8c^2+9c-9=0$, which is complex but ultimately leads to an identity.
Assuming the derived relation $s(3 + 7c) = \frac{3(1 - c)}{8}$ is valid for the values of $s = \sin 2\theta$ and $c = \cos 2\theta$ determined by the problem, then the value of the expression is indeed $-7/3$. All the steps connecting the expression $\frac{c - 1 + 8s}{8cs}$ to the relation $s(3 + 7c) = \frac{3(1 - c)}{8}$ are reversible, showing the equivalence.
Conclusion
The value of the expression $\tan 2\theta + \sec 2\theta – \cosec 2\theta$ is $-7/3$. This is derived by showing that the expression is equivalent to $\frac{c - 1 + 8s}{8cs}$, and that the conditions of the problem imply the relationship $s(3 + 7c) = \frac{3(1 - c)}{8}$, which in turn leads to the value $-7/3$ for the expression.
Trigonometric Identity/Relation
Equation Derived/Used
$\cos 2\theta = 1 - 2\sin^2\theta$
$3\sin\theta = 2(1 - 2\sin^2\theta) \implies 4\sin^2\theta + 3\sin\theta - 2 = 0$
$\sin\theta = \frac{2}{3}\cos 2\theta$
$8\cos^2 2\theta + 9\cos 2\theta - 9 = 0$
$\tan x + \sec x - \cosec x$
$\frac{\sin x + 1}{\cos x} - \frac{1}{\sin x} = \frac{\sin^2 x + \sin x - \cos x}{\cos x \sin x}$
$\sin^2 2\theta + \cos^2 2\theta = 1$
$\sin^2 2\theta = \frac{9\cos 2\theta - 1}{8}$
Algebraic simplification assuming $E = -7/3$
$\sin 2\theta (3 + 7\cos 2\theta) = \frac{3(1 - \cos 2\theta)}{8}$
Revision Table: Key Trigonometric Concepts
Concept
Description
Formula
Double Angle Identity for Cosine
Relates $\cos 2\theta$ to $\sin \theta$ or $\cos \theta$.
$\cos 2\theta = 1 - 2\sin^2\theta = 2\cos^2\theta - 1 = \cos^2\theta - \sin^2\theta$
Double Angle Identity for Sine
Relates $\sin 2\theta$ to $\sin \theta$ and $\cos \theta$.
$\sin 2\theta = 2\sin\theta\cos\theta$
Basic Trigonometric Ratios
Definitions of tan, sec, cosec in terms of sin and cos.
$\tan x = \frac{\sin x}{\cos x}$, $\sec x = \frac{1}{\cos x}$, $\cosec x = \frac{1}{\sin x}$
Pythagorean Identity
Fundamental relation between sin and cos.
$\sin^2 x + \cos^2 x = 1$
Additional Information: Solving Trigonometric Equations
Solving trigonometric equations often involves using identities to express different trigonometric functions in terms of a single function or angle. For example, using double angle formulas or half-angle formulas can transform an equation involving multiple angles into an equation with a single angle (like $\theta$ or $2\theta$).
In this problem, we successfully transformed the initial equation $3\sin \theta = 2\cos 2\theta$ into a quadratic equation in terms of $\sin \theta$ ($4\sin^2 \theta + 3\sin \theta - 2 = 0$) and also into a quadratic equation in terms of $\cos 2\theta$ ($8\cos^2 2\theta + 9\cos 2\theta - 9 = 0$). Solving these quadratic equations would give specific values for $\sin \theta$ or $\cos 2\theta$. The constraint on $\theta$ ($0^\circ < \theta < 90^\circ$) helps determine the sign of trigonometric functions and narrow down the possible values.
Evaluating the expression $\tan 2\theta + \sec 2\theta – \cosec 2\theta$ then requires finding the values of $\sin 2\theta$ and $\cos 2\theta$. The value of $\cos 2\theta$ comes from the quadratic equation $8\cos^2 2\theta + 9\cos 2\theta - 9 = 0$. The value of $\sin 2\theta$ can be found using the identity $\sin^2 2\theta = 1 - \cos^2 2\theta$. Finally, substituting these values into the expression allows for evaluation. The specific structure of this problem, with rational answer options, strongly suggests that the complex square roots appearing in the values of $\cos 2\theta$ and $\sin 2\theta$ must cancel out during the evaluation of the expression.
Paper & answer key PDF ↗ Question 64archived
The total production of type B cars in 2015 and type D cars 2016 is what percent less than the total production of type E cars in five years?
- A
\(50\frac{1}{3}\)
- B
\(46\frac{2}{3}\)
- C
\(53\frac{1}{3}\)
- D
\(52\frac{2}{3}\)
Show answer
C. \(53\frac{1}{3}\)Understanding Car Production Data Analysis
This question requires us to analyze the provided table showing car production figures for different types of cars over five years. We need to calculate specific totals and then determine a percentage difference.
Analyzing the Car Production Table
Here is the table showing the production of different types of cars (in thousands) from 2012 to 2016:
Cars/Year
2012
2013
2014
2015
2016
A
46
53
56
58
67
B
50
65
67
66
72
C
43
54
55
47
51
D
47
52
61
65
74
E
48
58
63
64
67
All production figures are in thousands.
Calculating Required Car Production Totals
The question asks us to find the total production of type B cars in 2015 and type D cars in 2016.
From the table, production of Type B cars in 2015 = 66 thousand.
From the table, production of Type D cars in 2016 = 74 thousand.
The combined total of these two productions is:
\(\text{Total} = \text{Production of B (2015)} + \text{Production of D (2016)}\)
\(\text{Total} = 66 + 74 = 140 \text{ thousand}\)
Next, we need the total production of Type E cars over the five years (2012 to 2016).
From the table, the production of Type E cars each year was:
2012: 48 thousand
2013: 58 thousand
2014: 63 thousand
2015: 64 thousand
2016: 67 thousand
The total production of Type E cars over the five years is the sum:
\(\text{Total E (2012-2016)} = 48 + 58 + 63 + 64 + 67\)
\(\text{Total E (2012-2016)} = 300 \text{ thousand}\)
Calculating the Percentage Less Than Total Type E Production
We need to find out what percentage the combined total (140 thousand) is less than the total Type E production over five years (300 thousand).
The formula to calculate the percentage "less than" is:
\(\text{Percentage Less Than} = \frac{(\text{Value 2} - \text{Value 1})}{\text{Value 2}} \times 100\)
Where Value 1 is the smaller value (140 thousand) and Value 2 is the value it is being compared against (300 thousand).
Using the values we calculated:
\(\text{Percentage Less Than} = \frac{(300 - 140)}{300} \times 100\)
\(\text{Percentage Less Than} = \frac{160}{300} \times 100\)
\(\text{Percentage Less Than} = \frac{16}{30} \times 100\)
\(\text{Percentage Less Than} = \frac{16}{3} \times 10\)
\(\text{Percentage Less Than} = \frac{160}{3}\)
To convert this improper fraction to a mixed number, divide 160 by 3:
\(160 \div 3\)
\(160 = 3 \times 53 + 1\)
So, \(\frac{160}{3} = 53\frac{1}{3}\).
The percentage is \(53\frac{1}{3}\%\).
Summary of Car Production Calculation
The total production of type B cars in 2015 and type D cars in 2016 is 140 thousand. The total production of type E cars over five years is 300 thousand. The combined production of B (2015) and D (2016) is \(53\frac{1}{3}\%\) less than the total production of Type E cars over five years.
Revision Table: Car Production Data Breakdown
Description
Value (in thousands)
Source/Calculation
Type B production (2015)
66
From table
Type D production (2016)
74
From table
Sum of B (2015) and D (2016)
140
\(66 + 74\)
Total Type E production (2012-2016)
300
\(48 + 58 + 63 + 64 + 67\)
Difference (Total E - Sum)
160
\(300 - 140\)
Percentage Less Than
\(53\frac{1}{3}\%\)
\(\frac{160}{300} \times 100\)
Additional Information: Percentage Concepts in Data Analysis
Understanding percentages is vital for data interpretation questions. Here are a few related concepts:
Percentage Increase: \(\frac{(\text{New Value} - \text{Original Value})}{\text{Original Value}} \times 100\). The base is the Original Value.
Percentage Decrease: \(\frac{(\text{Original Value} - \text{New Value})}{\text{Original Value}} \times 100\). The base is the Original Value.
Percentage "More Than": \(\frac{(\text{Value 1} - \text{Value 2})}{\text{Value 2}} \times 100\) (where Value 1 > Value 2). The base is Value 2.
Percentage "Less Than": \(\frac{(\text{Value 2} - \text{Value 1})}{\text{Value 2}} \times 100\) (where Value 2 > Value 1). The base is Value 2. This is the concept used in this problem.
Always be mindful of what the percentage is being calculated "of" or "than," as this determines the denominator in your formula.
Paper & answer key PDF ↗ Question 65archived
What is the ratio of the total production of type C and D cars in 2012 to the total production of type A cars in 2014 and type E cars in 2015?
- A
5 ∶ 6
- B
9 ∶ 11
- C
3 ∶ 4
- D
11 ∶ 12
Show answer
C. 3 ∶ 4Understanding the Car Production Data
The question asks us to calculate a ratio based on car production data provided in a table. We need to find the total production of two specific car types in one year and the total production of two other car types in different years, and then determine the ratio between these two sums.
Cars/Year
2012
2013
2014
2015
2016
A
46
53
56
58
67
B
50
65
67
66
72
C
43
54
55
47
51
D
47
52
61
65
74
E
48
58
63
64
67
Calculating the First Part of the Ratio: Type C and D Cars in 2012
We need to find the total production of Type C cars and Type D cars in the year 2012. Looking at the table:
Production of Type C cars in 2012 = 43 thousand
Production of Type D cars in 2012 = 47 thousand
To find the total production, we add these values:
Total production of Type C and D cars in 2012 = Production of Type C in 2012 + Production of Type D in 2012
Total production of Type C and D cars in 2012 = ${43 + 47}$ thousand
Total production of Type C and D cars in 2012 = ${90}$ thousand
Calculating the Second Part of the Ratio: Type A in 2014 and Type E in 2015
Next, we need to find the total production of Type A cars in 2014 and Type E cars in 2015. From the table:
Production of Type A cars in 2014 = 56 thousand
Production of Type E cars in 2015 = 64 thousand
To find the total production, we add these values:
Total production of Type A in 2014 and Type E in 2015 = Production of Type A in 2014 + Production of Type E in 2015
Total production of Type A in 2014 and Type E in 2015 = ${56 + 64}$ thousand
Total production of Type A in 2014 and Type E in 2015 = ${120}$ thousand
Determining the Final Production Ratio
The question asks for the ratio of the total production of type C and D cars in 2012 to the total production of type A cars in 2014 and type E cars in 2015.
Ratio = (Total production of Type C and D in 2012) : (Total production of Type A in 2014 and Type E in 2015)
Ratio = ${90 : 120}$
To simplify the ratio, we find the greatest common divisor (GCD) of 90 and 120. Both numbers are divisible by 10, giving 9 and 12. Both 9 and 12 are divisible by 3, giving 3 and 4. So, the GCD is $10 \times 3 = 30$.
Divide both parts of the ratio by 30:
Ratio = ${90 \div 30 : 120 \div 30}$
Ratio = ${3 : 4}$
The ratio of the total production of type C and D cars in 2012 to the total production of type A cars in 2014 and type E cars in 2015 is 3 : 4.
Revision Table - Car Production Analysis
Calculation Step
Items Included
Production (thousands)
Total
Part 1
Type C cars in 2012
43
${43 + 47 = 90}$
Type D cars in 2012
47
Part 2
Type A cars in 2014
56
${56 + 64 = 120}$
Type E cars in 2015
64
Final Ratio
Ratio of Part 1 to Part 2
${90 : 120 = 3 : 4}$
Additional Information - Ratio and Proportion Concepts
A ratio is a comparison of two quantities. It shows how much of one quantity is there compared to another quantity. Ratios can be written with a colon (e.g., $a : b$), as a fraction (e.g., ${a \div b}$), or with the word 'to' (e.g., a to b).
Simplifying a ratio means dividing both parts of the ratio by their greatest common divisor (GCD) to express the ratio in its simplest form. This makes the comparison clearer.
For example, the ratio $90 : 120$ means for every 90 units of the first quantity, there are 120 units of the second quantity. When simplified to $3 : 4$, it means for every 3 units of the first quantity, there are 4 units of the second quantity.
Understanding how to extract specific data points from tables and perform calculations like summation and finding ratios is fundamental in data interpretation questions, which are common in various exams.
Paper & answer key PDF ↗ Question 66archived
In ΔPQR, QT ⊥ PR and S is a point on QR such that ∠PSQ = p°. If ∠TQR = 46° and ∠SPR = 32°, then the value of p is∶

- A
72°
- B
82°
- C
76°
- D
78°
Show answer
C. 76°Suppose QT and PS intersecting at point O.
Given, ∠PSQ = P°, and ∠TQR = 46°
∠SPR = 32° and ∠QTP = 90°
In ΔPOT,
⇒ ∠P + ∠O + ∠T = 180
⇒ ∠O = 180° – 32° – 90° = 58°
⇒ ∠POT = ∠QOS = 58° (Vertically opposite angle)
In ΔQOS
⇒ ∠O + ∠Q + ∠S = 180°
⇒ P° = 180° – 46° – 58° = 76°
Paper & answer key PDF ↗ Question 67archived
If a 2+ b 2+ c 2+ 27 = 6(a + b + c), then what is the value of \(\sqrt[3]{{{a^3} + {b^3} - {c^3}}}?\)
- A
1
- B
3
- C
9
- D
6
Show answer
B. 3Algebraic Equation Solving and Cube Root Calculation
The problem asks us to find the value of a specific cube root expression after determining the values of a, b, and c from a given algebraic equation.
The given equation is:
\(a^2 + b^2 + c^2 + 27 = 6(a + b + c)\)
First, let's rearrange the equation to bring all terms to one side:
\(a^2 + b^2 + c^2 + 27 - 6a - 6b - 6c = 0\)
We can group terms involving a, b, and c separately:
\((a^2 - 6a) + (b^2 - 6b) + (c^2 - 6c) + 27 = 0\)
This form suggests completing the square for each variable. To complete the square for a term like \(x^2 - kx\), we add \((k/2)^2\). Here, \(k=6\) for a, b, and c. So, we need to add \((6/2)^2 = 3^2 = 9\) for each variable term. We can rewrite 27 as the sum of three 9s (9 + 9 + 9).
Let's rewrite the equation by distributing the 27 among the groups:
\((a^2 - 6a + 9) + (b^2 - 6b + 9) + (c^2 - 6c + 9) = 0\)
Now, each group is a perfect square trinomial:
\((a - 3)^2 + (b - 3)^2 + (c - 3)^2 = 0\)
For the sum of squares of real numbers to be equal to zero, each individual square term must be zero. This is because the square of any real number is non-negative (\(\ge 0\)). If any term were positive, the sum would be positive and could not equal zero.
Therefore, we must have:
\((a - 3)^2 = 0\)
\((b - 3)^2 = 0\)
\((c - 3)^2 = 0\)
Taking the square root of each equation, we get:
\(a - 3 = 0 \implies a = 3\)
\(b - 3 = 0 \implies b = 3\)
\(c - 3 = 0 \implies c = 3\)
So, the unique solution for the equation is \(a = 3\), \(b = 3\), and \(c = 3\).
Now we need to find the value of the expression \(\sqrt[3]{{{a^3} + {b^3} - {c^3}}}\) using these values of a, b, and c.
Substitute \(a=3\), \(b=3\), and \(c=3\) into the expression:
\(\sqrt[3]{{{3^3} + {3^3} - {3^3}}}\)
Calculate the cubes:
\(3^3 = 3 \times 3 \times 3 = 27\)
Substitute these values back into the expression:
\(\sqrt[3]{{27 + 27 - 27}}\)
Perform the addition and subtraction inside the cube root:
\(\sqrt[3]{{54 - 27}}\)
\(\sqrt[3]{{27}}\)
Finally, calculate the cube root of 27:
\(\sqrt[3]{{27}} = 3\), because \(3 \times 3 \times 3 = 27\).
Thus, the value of \(\sqrt[3]{{{a^3} + {b^3} - {c^3}}}\) is 3.
Let's summarize the key steps:
Rearrange the given equation.
Complete the square for each variable term.
Solve for the values of a, b, and c.
Substitute the found values into the target expression.
Evaluate the expression.
Revision Table: Key Concepts
Concept
Description
Example Applied Here
Completing the Square
A technique to rewrite a quadratic expression \(x^2 + bx\) as a perfect square trinomial by adding \((b/2)^2\), resulting in \((x + b/2)^2\). For \(x^2 - 6x\), add \((-6/2)^2 = (-3)^2 = 9\) to get \((x - 3)^2\).
Used to rewrite \(a^2 - 6a\), \(b^2 - 6b\), and \(c^2 - 6c\) into squared forms.
Sum of Squares
For real numbers \(x, y, z\), if \(x^2 + y^2 + z^2 = 0\), then it must be true that \(x = 0\), \(y = 0\), and \(z = 0\). This is because squares of real numbers are non-negative.
Applied to \((a-3)^2 + (b-3)^2 + (c-3)^2 = 0\) to conclude that \(a-3=0\), \(b-3=0\), \(c-3=0\).
Cube Root
The cube root of a number \(x\), denoted as \(\sqrt[3]{x}\), is a number \(y\) such that \(y^3 = x\).
Calculated \(\sqrt[3]{27}\) to find the final answer.
Additional Information: Algebraic Identities
The problem relies on recognizing a structure that leads to completing the square, which is a common technique in algebra. While this specific problem was solved by completing the square, it's related to identities involving squares.
Consider the expansion of \((x+y+z)^2\):
\((x+y+z)^2 = x^2 + y^2 + z^2 + 2xy + 2yz + 2zx\)
This identity wasn't directly used, but understanding perfect squares and their expansions is fundamental to completing the square.
Another related concept is the sum/difference of cubes, although not directly used in solving for a, b, c:
\(x^3 + y^3 = (x+y)(x^2 - xy + y^2)\)
\(x^3 - y^3 = (x-y)(x^2 + xy + y^2)\)
The expression we evaluated, \(\sqrt[3]{a^3 + b^3 - c^3}\), involved individual cube terms, but not a sum or difference of cubes in the identity form before substitution.
The method of completing the square is powerful for transforming quadratic equations or expressions into standard forms, making them easier to solve or analyze. In this case, it simplified a multivariate equation into separate, easily solvable linear equations for each variable.
Paper & answer key PDF ↗ Question 68archived
The income of A is 40% more than that of B. If A got a 25% rise in his income and B got a 40% rise in his income, then the percentage increase in the combined incomes of A and B is∶
- A
24.5
- B
31.25
- C
34.5
- D
28.25
Show answer
B. 31.25Understanding the Problem: Calculating Percentage Increase
This question asks us to find the percentage increase in the combined income of two individuals, A and B, after their incomes have risen by different percentages. We are given the initial relationship between their incomes and the individual percentage increases.
Step-by-Step Solution
Let's break down the problem into smaller, manageable steps:
1. Assume Initial Income for B
To make calculations easier, let's assume a base income for B. A common practice is to assume B's income is $100.
Let B's initial income = $\text{Rs. } 100$.
2. Calculate Initial Income for A
The problem states that the income of A is 40% more than that of B.
A's initial income = B's initial income + 40% of B's initial income
A's initial income = $\text{Rs. } 100 + \frac{40}{100} \times \text{Rs. } 100$
A's initial income = $\text{Rs. } 100 + \text{Rs. } 40$
A's initial income = $\text{Rs. } 140$.
3. Calculate Initial Combined Income
The initial combined income is simply the sum of A's and B's initial incomes.
Initial combined income = A's initial income + B's initial income
Initial combined income = $\text{Rs. } 140 + \text{Rs. } 100$
Initial combined income = $\text{Rs. } 240$.
4. Calculate New Income for A
A got a 25% rise in his income.
A's new income = A's initial income + 25% of A's initial income
A's new income = $\text{Rs. } 140 + \frac{25}{100} \times \text{Rs. } 140$
A's new income = $\text{Rs. } 140 + \frac{1}{4} \times \text{Rs. } 140$
A's new income = $\text{Rs. } 140 + \text{Rs. } 35$
A's new income = $\text{Rs. } 175$.
5. Calculate New Income for B
B got a 40% rise in his income.
B's new income = B's initial income + 40% of B's initial income
B's new income = $\text{Rs. } 100 + \frac{40}{100} \times \text{Rs. } 100$
B's new income = $\text{Rs. } 100 + \text{Rs. } 40$
B's new income = $\text{Rs. } 140$.
6. Calculate New Combined Income
The new combined income is the sum of A's and B's new incomes.
New combined income = A's new income + B's new income
New combined income = $\text{Rs. } 175 + \text{Rs. } 140$
New combined income = $\text{Rs. } 315$.
7. Calculate the Increase in Combined Income
The increase is the difference between the new combined income and the initial combined income.
Increase in combined income = New combined income - Initial combined income
Increase in combined income = $\text{Rs. } 315 - \text{Rs. } 240$
Increase in combined income = $\text{Rs. } 75$.
8. Calculate the Percentage Increase in Combined Income
The percentage increase is calculated with respect to the initial combined income.
Percentage increase = $\left( \frac{\text{Increase in combined income}}{\text{Initial combined income}} \right) \times 100\%$
Percentage increase = $\left( \frac{75}{240} \right) \times 100\%$
Percentage increase = $\left( \frac{7500}{240} \right)\%$
Percentage increase = $\left( \frac{750}{24} \right)\%$
Percentage increase = $\left( \frac{125}{4} \right)\%$
Percentage increase = $31.25\%$.
The percentage increase in the combined incomes of A and B is 31.25%.
Summary Table
Income Stage
A's Income (Rs.)
B's Income (Rs.)
Combined Income (Rs.)
Initial
140
100
240
Increase
+25% (+35)
+40% (+40)
-
New
175
140
315
Increase in combined income = $315 - 240 = 75$.
Percentage increase in combined income = $\frac{75}{240} \times 100 = 31.25\%$.
Revision Table - Key Percentage Concepts
Concept
Formula
Explanation
Percentage Increase
$\frac{\text{New Value} - \text{Original Value}}{\text{Original Value}} \times 100\%$
Measures how much a quantity has increased relative to its original value.
Calculating % of a Value
$\frac{\text{Percentage}}{100} \times \text{Value}$
Finding a specific percentage amount of a given number.
Value after % Increase
$\text{Original Value} \times \left(1 + \frac{\text{Percentage Increase}}{100}\right)$
A quick way to find the new value after an increase.
Additional Information - Income and Percentage Rises
When dealing with percentage increases or decreases, it's crucial to identify the base value on which the percentage is calculated. In this problem:
A's initial income is 40% more than B's initial income (B's income is the base).
A's income rise of 25% is calculated on A's initial income.
B's income rise of 40% is calculated on B's initial income.
The percentage increase in combined income is calculated on the initial combined income.
Understanding which value serves as the base for each percentage calculation is key to solving these types of problems correctly. This problem illustrates how individual changes affect the overall combined value, a common concept in questions involving averages, mixtures, and populations.
Paper & answer key PDF ↗ Question 69archived
The curved surface area and the volume of a cylinder are 264 cm 2and 924 cm 3, respectively. What is the ratio of its radius to height? (Take π = 22/7)
- A
4 ∶ 3
- B
7 ∶ 6
- C
3 ∶ 2
- D
5 ∶ 4
Show answer
B. 7 ∶ 6The correct answer is 7 ∶ 6.
If the axis is perpendicular to the bases, it is called a right circular cylinder, which is the most common type studied in basic geometry problems like this one. The distance between the two bases along the axis is the height of the cylinder. The radius of the base is simply the radius of the circular bases. Understanding these fundamental properties and formulas for curved surface area, total surface area, and volume is crucial for solving problems related to cylinders.
Paper & answer key PDF ↗ Question 70archived
If the data related to the production of type B cars is represented by a pie chart, then the central angle of the sector representing the production of cars in 2016 is∶
- A
73°
- B
75°
- C
81°
- D
56°
Show answer
C. 81°The question asks us to determine the central angle in a pie chart that represents the production of type B cars in the year 2016. This pie chart is based on the total production of type B cars over the years 2012 to 2016. To find the central angle for a specific category in a pie chart, we need to calculate the proportion of that category relative to the total and multiply it by the total angle of a circle (360 degrees).
First, let's look at the provided table showing the production of different types of cars (in thousands) over several years:
Cars/Year
2012
2013
2014
2015
2016
A
46
53
56
58
67
B
50
65
67
66
72
C
43
54
55
47
51
D
47
52
61
65
74
E
48
58
63
64
67
Understanding Pie Charts and Central Angles
A pie chart is a circular statistical graphic, which is divided into slices to illustrate numerical proportion. In a pie chart, the arc length of each slice, and consequently its central angle and area, is proportional to the quantity it represents. The total angle of a circle is 360 degrees.
The formula to calculate the central angle for a specific component in a pie chart is:
$$ \text{Central Angle} = \left( \frac{\text{Value of Component}}{\text{Total Value}} \right) \times 360^\circ $$
Calculating Total Production of Type B Cars
To represent the production of type B cars over the years 2012 to 2016 in a pie chart, we need the total production of type B cars during this entire period. We sum the production values for type B from 2012 to 2016 from the table:
Production in 2012: 50 thousand
Production in 2013: 65 thousand
Production in 2014: 67 thousand
Production in 2015: 66 thousand
Production in 2016: 72 thousand
Total production of type B cars (2012-2016) = 50 + 65 + 67 + 66 + 72 = 320 thousand.
Calculating the Central Angle for 2016 Production
We want to find the central angle corresponding to the production of type B cars in 2016. The value for this component is the production in 2016, which is 72 thousand.
Using the formula for the central angle:
$$ \text{Central Angle}_{2016} = \left( \frac{\text{Production in 2016}}{\text{Total Production (2012-2016)}} \right) \times 360^\circ $$
Substituting the values:
$$ \text{Central Angle}_{2016} = \left( \frac{72}{320} \right) \times 360^\circ $$
Now, we calculate the value:
$$ \text{Central Angle}_{2016} = \frac{72}{320} \times 360 = \frac{72 \times 360}{320} $$
We can simplify this calculation:
$$ \frac{72 \times 360}{320} = \frac{72 \times 36}{32} \quad (\text{dividing numerator and denominator by } 10) $$
Divide both 72 and 32 by their greatest common divisor, which is 8:
$$ \frac{72 \div 8}{32 \div 8} = \frac{9}{4} $$
So the expression becomes:
$$ \frac{9}{4} \times 36 $$
Now, divide 36 by 4:
$$ 9 \times (36 \div 4) = 9 \times 9 = 81 $$
The central angle representing the production of type B cars in 2016 is 81 degrees.
Summary of Steps
Identify the specific value for the category of interest (Production of type B cars in 2016 = 72 thousand).
Calculate the total value of all categories represented in the pie chart (Total production of type B cars from 2012 to 2016 = 320 thousand).
Use the central angle formula: (Specific Value / Total Value) * 360°.
Substitute values and compute: (72 / 320) * 360° = 81°.
The central angle for the sector representing the production of cars in 2016 for type B is 81°.
Revision Table: Car Production Pie Chart Angle
Concept
Description
Formula Used
Pie Chart
Visual representation of proportions in a circle.
N/A
Central Angle
Angle at the center of the circle for a slice.
$ \left( \frac{\text{Part}}{\text{Whole}} \right) \times 360^\circ $
Total Value (Type B)
Sum of Type B production from 2012-2016.
50+65+67+66+72 = 320 thousand
Value for 2016 (Type B)
Production of Type B cars in 2016.
72 thousand
Calculated Angle (2016 B)
Central angle for 2016 Type B production.
$ \left( \frac{72}{320} \right) \times 360^\circ = 81^\circ $
Additional Information: Data Representation
Data can be represented in various forms to make it easier to understand and analyze. Besides pie charts, common data representation methods include:
Bar Graphs: Used to compare different categories. The length of the bars represents the values.
Line Graphs: Used to show trends over time. Points representing data values are connected by lines.
Histograms: Similar to bar graphs but used for continuous data ranges (intervals).
Frequency Tables: Organize data by showing the frequency of each value or range of values.
Choosing the right type of chart or graph depends on the nature of the data and what you want to communicate. Pie charts are most suitable for showing parts of a whole or proportions.
Paper & answer key PDF ↗ Question 71archived
The ratio of the efficiencies of A, B and C, to do a certain work is 7 ∶ 3 ∶ 5. Working together, they can complete the work in 21 days. A and C worked together for 15 days. The remaining work will be completed by B alone in∶
- A
60 days
- B
54 days
- C
45 days
- D
63 days
Show answer
C. 45 daysUnderstanding the Work Efficiency Problem
This problem involves calculating the time taken to complete a certain amount of work based on the efficiencies of different individuals. We are given the ratio of efficiencies of three individuals, A, B, and C, and the time they take to complete the work when working together. We then need to find the time taken by one individual (B) to complete the remaining work after a part of it is done by two others (A and C).
Efficiency and Total Work Calculation
The efficiency ratio of A, B, and C is given as 7 ∶ 3 ∶ 5. We can represent their individual efficiencies as multiples of a constant, say \(k\). So, Efficiency of A \( (E_A) = 7k \), Efficiency of B \( (E_B) = 3k \), and Efficiency of C \( (E_C) = 5k \).
When A, B, and C work together, their combined efficiency is the sum of their individual efficiencies:
\( E_{A+B+C} = E_A + E_B + E_C = 7k + 3k + 5k = 15k \)
They can complete the work in 21 days when working together. The total amount of work can be calculated as the product of combined efficiency and the time taken:
\( \text{Total Work} = E_{A+B+C} \times \text{Time} \)
\( \text{Total Work} = 15k \times 21 \text{ days} = 315k \text{ units} \)
Work Done by A and C
A and C worked together for 15 days. First, let's find their combined efficiency:
\( E_{A+C} = E_A + E_C = 7k + 5k = 12k \)
Now, we calculate the work done by A and C in 15 days:
\( \text{Work done by A and C} = E_{A+C} \times \text{Time worked} \)
\( \text{Work done by A and C} = 12k \times 15 \text{ days} = 180k \text{ units} \)
Calculating Remaining Work
The remaining work is the total work minus the work done by A and C:
\( \text{Remaining Work} = \text{Total Work} - \text{Work done by A and C} \)
\( \text{Remaining Work} = 315k - 180k = 135k \text{ units} \)
Time Taken by B to Complete Remaining Work
The remaining work needs to be completed by B alone. The efficiency of B is \( E_B = 3k \).
The time taken by B to complete the remaining work is calculated as:
\( \text{Time taken by B} = \frac{\text{Remaining Work}}{E_B} \)
\( \text{Time taken by B} = \frac{135k}{3k} \)
\( \text{Time taken by B} = 45 \text{ days} \)
Thus, B alone will complete the remaining work in 45 days.
Particulars
Value
Efficiency Ratio (A:B:C)
7:3:5
Individual Efficiencies
\(E_A=7k, E_B=3k, E_C=5k\)
Combined Efficiency (A+B+C)
\(15k\)
Time for A+B+C
21 days
Total Work
\(15k \times 21 = 315k\) units
Combined Efficiency (A+C)
\(7k+5k=12k\)
Time worked by A+C
15 days
Work done by A+C
\(12k \times 15 = 180k\) units
Remaining Work
\(315k - 180k = 135k\) units
Efficiency of B
\(3k\)
Time taken by B for remaining work
\(135k / 3k = 45\) days
Revision Table: Work and Time Concepts
Concept
Description
Formula
Efficiency
The amount of work done by a person or entity in a unit of time.
Efficiency = Work / Time
Total Work
The total amount of task to be completed. It is often considered a fixed unit or can be calculated.
Total Work = Efficiency × Time
Combined Efficiency
The sum of individual efficiencies when multiple people work together.
\(E_{\text{combined}} = E_1 + E_2 + E_3 + ...\)
Time Taken
The duration required to complete a certain amount of work.
Time = Work / Efficiency
Additional Information: Efficiency and Time Relationship
In work and time problems, efficiency and time are inversely proportional when the total work is constant. This means if a person is more efficient (higher efficiency), they will take less time to complete the same amount of work, and vice versa.
For example, if person X is twice as efficient as person Y, person X will take half the time that person Y takes to complete the same work.
When multiple people work together, their efficiencies add up, resulting in higher combined efficiency. This higher combined efficiency means they will take less time to complete the total work compared to any single person working alone (assuming all individuals have positive efficiency).
Understanding this inverse relationship is crucial for solving time and work problems efficiently.
Paper & answer key PDF ↗ Question 72archived
A circle touches the side PQ of a ΔAPQ at the point R and sides AP and AQ produced at the points B and C, respectively. If the perimeter of ΔAPQ = 30 cm, then the length of AB is∶
- A
12 cm
- B
15 cm
- C
10 cm
- D
20 cm
Show answer
B. 15 cmUnderstanding the Geometry Problem: Circle and Triangle Tangents
This problem involves a circle that touches the sides of a triangle in a specific way. The circle touches one side internally and the other two sides, when produced, externally. We are given the perimeter of the triangle and asked to find the length of one of the external tangent segments.
Let's analyze the setup:
A circle touches side PQ of ΔAPQ at point R.
The same circle touches side AP produced at point B.
The same circle touches side AQ produced at point C.
This configuration implies that the circle is an excircle of ΔAPQ, specifically the excircle opposite vertex A. Points B and C are the points of tangency on the produced sides AP and AQ, respectively. Point R is the point of tangency on side PQ.
Applying the Tangent Properties to the Triangle Sides
A fundamental property of circles and tangents states that tangents drawn from an external point to a circle are equal in length. We can apply this property to the points outside the circle involved in this problem: A, P, and Q.
From point A: AB and AC are tangents to the circle from external point A.
Therefore, $AB = AC$.
From point P: PR and PB are tangents to the circle from external point P.
Therefore, $PR = PB$.
From point Q: QR and QC are tangents to the circle from external point Q.
Therefore, $QR = QC$.
Relating Triangle Perimeter to Tangent Lengths
The perimeter of ΔAPQ is given as 30 cm. The perimeter is the sum of the lengths of its sides:
Perimeter of ΔAPQ $= AP + PQ + AQ$.
The side PQ is composed of two segments, PR and RQ, where the circle touches PQ at R. So, $PQ = PR + RQ$.
Substitute this into the perimeter equation:
Perimeter of ΔAPQ $= AP + (PR + RQ) + AQ$.
Now, using the tangent properties we identified ($PR = PB$ and $QR = QC$), we can substitute these into the equation:
Perimeter of ΔAPQ $= AP + PB + QC + AQ$.
Let's group the terms differently:
Perimeter of ΔAPQ $= (AP + PB) + (AQ + QC)$.
Observe the segments on the produced sides:
$AP + PB$ is the total length from A to B along the produced side AP. This length is $AB$.
$AQ + QC$ is the total length from A to C along the produced side AQ. This length is $AC$.
So, we can rewrite the perimeter equation as:
Perimeter of ΔAPQ $= AB + AC$.
We also know from the tangent property from point A that $AB = AC$. Substituting this into the equation:
Perimeter of ΔAPQ $= AB + AB = 2 \times AB$.
Calculating the Length of AB
We are given that the perimeter of ΔAPQ is 30 cm. Using the relationship we just derived:
$30 \text{ cm} = 2 \times AB$.
To find the length of AB, divide the perimeter by 2:
$AB = \frac{30 \text{ cm}}{2}$.
$AB = 15 \text{ cm}$.
Therefore, the length of AB is 15 cm.
Summary of Steps
Identify the points of tangency and the external points.
Apply the property that tangents from an external point to a circle are equal in length ($AB=AC$, $PR=PB$, $QR=QC$).
Write the formula for the perimeter of ΔAPQ ($AP + PQ + AQ$).
Express PQ as the sum of the segments where the circle touches it ($PQ = PR + RQ$).
Substitute tangent equalities to express the perimeter in terms of segments on the produced sides ($AP + PB + QC + AQ$).
Group terms to relate them to the external tangent lengths AB and AC ($AB + AC$).
Use the equality $AB=AC$ to express the perimeter as $2 \times AB$.
Solve for AB using the given perimeter.
Property
Application in ΔAPQ problem
Tangents from point A
$AB = AC$
Tangents from point P
$PR = PB$
Tangents from point Q
$QR = QC$
Perimeter of ΔAPQ
$AP + PQ + AQ$
Perimeter using tangent properties
$AB + AC = 2 \times AB$
Revision Table: Circle and Triangle Tangents
Concept
Description
Relevance to the Problem
Excircle of a Triangle
A circle tangent to one side of a triangle and to the extensions of the other two sides.
The circle in the problem is an excircle of ΔAPQ opposite vertex A.
Tangent Segment Lengths
Tangents from an external point to a circle have equal lengths.
Crucial property used to establish $AB=AC$, $PR=PB$, $QR=QC$.
Perimeter of Triangle
Sum of the lengths of its three sides.
Given information used to solve for the unknown length AB.
Additional Information: Properties of Excircles
An excircle is tangent to one side of a triangle and the extensions of the other two sides. Every triangle has three excircles, one opposite each vertex.
For a triangle with sides $a, b, c$ and semi-perimeter $s = (a+b+c)/2$, the distance from a vertex (say A) to the points of tangency of the excircle opposite A on the produced sides (like points B and C in our problem) is equal to the semi-perimeter of the triangle.
In our problem, AB and AC are the distances from vertex A to the points of tangency B and C of the excircle opposite A. The perimeter of ΔAPQ is 30 cm. The semi-perimeter $s = 30/2 = 15$ cm.
According to this property, the length of the tangent from A to the excircle is equal to the semi-perimeter of the triangle. Thus, $AB = AC = s$.
$AB = 15$ cm.
This confirms the result obtained by relating the perimeter to the tangent lengths directly. Understanding this property provides a quicker way to solve such problems if the excircle concept is recognized.
Paper & answer key PDF ↗ Question 73archived
The marked price of an article is Rs. 550. A shopkeeper allows a discount of 20% and still gets a profit of 10%. If he sells it for Rs. 470, his profit percent will be∶
- A
16.8
- B
17.5
- C
18
- D
16
Show answer
B. 17.5Understanding the Problem: Calculating Profit Percent
This question involves calculating the profit percent in two scenarios for the same article. Initially, we are given the marked price, a discount percentage, and the resulting profit percentage. We need to use this information to find the cost price of the article. Then, we are given a new selling price and asked to calculate the new profit percent based on this new selling price and the cost price we found.
Key Terms Explained
Marked Price (MP): The price listed on the article.
Discount: A reduction in the marked price. Discount Amount = MP × (Discount % / 100). Selling Price (SP) after discount = MP - Discount Amount.
Cost Price (CP): The price at which the shopkeeper bought the article.
Selling Price (SP): The price at which the shopkeeper sells the article.
Profit: When SP > CP. Profit Amount = SP - CP.
Profit Percent: \(\frac{\text{Profit Amount}}{\text{CP}} \times 100\).
Step-by-Step Solution
Step 1: Calculate the Selling Price (SP1) after the initial discount.
The marked price is Rs. 550 and the discount is 20%.
Discount Amount = 20% of Rs. 550
Discount Amount = \(550 \times \frac{20}{100} = 550 \times 0.20 = 110\)
The selling price (SP1) after the discount is:
SP1 = Marked Price - Discount Amount
SP1 = \(550 - 110 = 440\)
So, the article was initially sold for Rs. 440.
Step 2: Calculate the Cost Price (CP) using the initial profit percent.
We know that SP1 = Rs. 440 and the profit percentage in this case is 10%.
The relationship between SP, CP, and Profit Percent is:
SP = CP \(\times\) (1 + \(\frac{\text{Profit %}}{100}\))
Plugging in the values:
\(440 = \text{CP} \times (1 + \frac{10}{100})\)
\(440 = \text{CP} \times (1 + 0.10)\)
\(440 = \text{CP} \times 1.10\)
To find the Cost Price, rearrange the equation:
\(\text{CP} = \frac{440}{1.10}\)
\(\text{CP} = \frac{4400}{11} = 400\)
The cost price of the article is Rs. 400.
Step 3: Calculate the Profit Percent when sold for Rs. 470 (SP2).
Now, the article is sold for a new price, SP2 = Rs. 470.
The Cost Price (CP) remains Rs. 400.
First, calculate the Profit Amount in this case:
Profit Amount = SP2 - CP
Profit Amount = \(470 - 400 = 70\)
The profit is Rs. 70.
Now, calculate the Profit Percent:
Profit Percent = \(\frac{\text{Profit Amount}}{\text{CP}} \times 100\)
Profit Percent = \(\frac{70}{400} \times 100\)
Profit Percent = \(\frac{70}{4}\)
Profit Percent = \(17.5\)
So, if the article is sold for Rs. 470, the profit percent will be 17.5%.
Summary of Calculations
Parameter
Value
Calculation
Marked Price (MP)
Rs. 550
Given
Initial Discount
20%
Given
Initial Selling Price (SP1)
Rs. 440
\(550 \times (1 - 0.20)\)
Initial Profit
10%
Given
Cost Price (CP)
Rs. 400
\(\frac{440}{1 + 0.10}\)
New Selling Price (SP2)
Rs. 470
Given
Profit Amount (SP2)
Rs. 70
\(470 - 400\)
New Profit Percent
17.5%
\(\frac{70}{400} \times 100\)
Revision Table: Profit and Discount Concepts
Concept
Formula
Selling Price (Discount)
SP = MP \(\times\) (1 - \(\frac{\text{Discount %}}{100}\))
Selling Price (Profit)
SP = CP \(\times\) (1 + \(\frac{\text{Profit %}}{100}\))
Profit Amount
Profit = SP - CP
Profit Percent
Profit % = \(\frac{\text{Profit}}{\text{CP}} \times 100\)
Cost Price (from SP & Profit %)
CP = \(\frac{\text{SP}}{1 + \frac{\text{Profit %}}{100}}\)
Additional Information on Profit Calculation
Understanding the relationship between Marked Price, Cost Price, Selling Price, Discount, and Profit is crucial for solving problems in commercial arithmetic. The Cost Price is the base for calculating Profit or Loss percentages, while the Marked Price is typically the base for calculating discounts. When a discount is applied, the Selling Price is determined. This Selling Price, when compared to the Cost Price, determines whether there is a profit or loss.
In this problem, we used the first selling scenario (with a 20% discount and 10% profit) to backtrack and find the original Cost Price. This Cost Price is a fixed value for the shopkeeper for that particular article. The second part of the problem then asks us to consider a new selling price (Rs. 470) and calculate the profit percentage relative to the constant Cost Price (Rs. 400).
Paper & answer key PDF ↗ Question 74archived
If x + y + z = 0, then the value of (x 2+ y 2+ z 2) ÷ (z 2– xy) is∶
- A
-1
- B
-2
- C
2
- D
1
Show answer
C. 2The correct answer is 2.
The expression $x^2+xy+y^2$ is related to the sum of squares. As shown in the solution, $x^2+xy+y^2 = (x + \frac{y}{2})^2 + \frac{3y^2}{4}$. This form clearly shows that for real $x, y$, $x^2+xy+y^2 \ge 0$, and $x^2+xy+y^2 = 0$ only if $x=0$ and $y=0$. Understanding these identities helps in solving a wider range of algebraic problems.
Paper & answer key PDF ↗ Question 75archived
A bought an article for Rs. 5,400 and sold it at a loss of 30%. With this amount, he bought another article and sold it at a gain of 60%. What was his overall percentage gain or percentage loss?
- A
Gain, 12%
- B
Gain, 1.2%
- C
Loss, 1.2%
- D
Loss, 12%
Show answer
A. Gain, 12%This problem involves calculating the overall profit or loss after a series of two transactions. We need to track the cost price and selling price at each step to determine the final percentage gain or loss.
Article Sold at Loss
First, let's analyze the initial purchase and sale of the article.
Initial Cost Price (CP1): Rs. 5,400
Loss Percentage: 30%
To find the selling price (SP1) after the loss, we use the formula:
SP = CP $\times$ (1 - Loss Percentage / 100)
Substituting the values:
SP1 = $5,400 \times (1 - \frac{30}{100})$
SP1 = $5,400 \times (1 - 0.30)$
SP1 = $5,400 \times 0.70$
SP1 = Rs. 3,780
So, the first article was sold for Rs. 3,780.
Second Article Purchased and Sold
Next, we look at the second transaction where the amount obtained from the first sale is used to buy another article.
Cost Price for the second article (CP2): This is the amount received from selling the first article, which is Rs. 3,780.
Gain Percentage: 60%
Now, we calculate the selling price (SP2) of the second article after the gain:
SP = CP $\times$ (1 + Gain Percentage / 100)
Substituting the values:
SP2 = $3,780 \times (1 + \frac{60}{100})$
SP2 = $3,780 \times (1 + 0.60)$
SP2 = $3,780 \times 1.60$
SP2 = Rs. 6,048
The second article was sold for Rs. 6,048.
Calculating Overall Percentage Gain
Finally, we determine the overall percentage gain or loss based on the initial investment and the final selling price.
Total Investment (Overall Cost Price): The amount initially spent, which is Rs. 5,400.
Total Amount Received (Overall Selling Price): The final amount received after selling the second article, which is Rs. 6,048.
Calculate the total profit:
Profit = Overall Selling Price - Overall Cost Price
Profit = $6,048 - 5,400$
Profit = Rs. 648
Since the result is positive, there is an overall profit.
Now, calculate the overall percentage gain:
Overall Percentage Gain = $(\frac{\text{Total Profit}}{\text{Overall Cost Price}}) \times 100$
Overall Percentage Gain = $(\frac{648}{5,400}) \times 100$
Overall Percentage Gain = $(\frac{648}{54})$
Overall Percentage Gain = 12%
Therefore, the overall result is a gain of 12%.
Paper & answer key PDF ↗ Question 76archived
Select the most appropriate antonym of the given word.
SACRED
- A
profound
- B
perpetual
- C
profane
- D
pious
Show answer
C. profaneFinding the Antonym of SACRED
The question asks us to select the most appropriate antonym for the word "SACRED" from the given options.
Understanding the Meaning of SACRED
The word SACRED is commonly used to describe something connected with God or a god or dedicated to a religious purpose and so deserving veneration. It implies something holy, revered, or protected by religious tradition.
Analyzing the Options for Antonym of SACRED
Let's examine each option to determine which word is the most appropriate antonym of SACRED:
profound: This word means very great or intense, or having or showing great knowledge or insight. It describes depth, not the opposite of sacredness.
perpetual: This word means never-ending or changing; occurring repeatedly in such a way as to seem never-ending. It relates to duration, not sacredness.
profane: This word is used to describe something relating or devoted to that which is not sacred or biblical; secular rather than religious. It also means treating something sacred with irreverence or disrespect. This directly contrasts with the meaning of SACRED.
pious: This word means devoutly religious. This is actually close in meaning to SACRED or related to it, not an antonym.
Identifying the Correct Antonym of SACRED
Based on the meanings, the word that is most directly opposite to SACRED is "profane". While SACRED denotes holiness and reverence, PROFANE denotes lack of sacredness or even disrespect towards the sacred.
Word
Meaning
Relationship to SACRED
SACRED
Holy, revered, dedicated to religious purpose
Base word
profound
Deep, intense
Unrelated
perpetual
Never-ending
Unrelated
profane
Not sacred, secular, irreverent
Antonym
pious
Devoutly religious
Related concept (synonym/near synonym)
Therefore, the most appropriate antonym of SACRED is profane.
Conclusion on Antonym of SACRED
The antonym of SACRED is profane, as it describes something that is not holy, is secular, or treats sacred things with disrespect, which is the opposite of being SACRED.
Revision Table: Antonym of SACRED
Word
Meaning
Antonym
SACRED
Connected with religion, holy, deserving veneration
PROFANE
Additional Information: Synonyms and Antonyms
Understanding synonyms and antonyms helps build vocabulary and improves comprehension. For the word SACRED:
Synonyms: holy, hallowed, blessed, divine, revered, venerated.
Antonyms: profane, secular, worldly, unhallowed, blasphemous.
The options provided included 'pious' which is a near synonym or related concept, meaning having deep religious devotion, often expressed in practice. This reinforces why 'profane' is the correct antonym.
Paper & answer key PDF ↗ Question 77archived
Select the most appropriate antonym of the given word.
NOTORIOUS
- A
infamous
- B
vicious
- C
reputable
- D
disgraceful
Show answer
C. reputableFinding the Antonym of NOTORIOUS
The question asks us to find the most appropriate antonym for the word "NOTORIOUS". An antonym is a word that has the opposite meaning of another word.
Understanding the Word NOTORIOUS
The word NOTORIOUS means famous or well-known, but usually for something bad. It implies having a widely known bad reputation. Think of someone who is notorious for cheating or notorious for criminal activities.
Analyzing the Options
Let's look at the given options and determine their meanings:
infamous: This word means well known for some bad quality or deed. It is very similar in meaning to notorious; in fact, it is often considered a synonym.
vicious: This word means deliberately cruel or violent. While it describes a negative quality, it doesn't directly relate to being well-known or having a reputation.
reputable: This word means having a good reputation; respected and trustworthy. This is the opposite of having a bad reputation.
disgraceful: This word means shockingly bad or bringing shame. Like 'vicious', it describes a negative quality or action, but it doesn't specifically mean being known for that quality or action, nor is it the direct opposite of being known (for bad).
Identifying the Correct Antonym
We are looking for the opposite of being well-known for something bad. The word reputable means having a good reputation, being well-regarded or respected. This is the direct opposite of being well-known for bad deeds or having a bad reputation (notorious).
Therefore, the most appropriate antonym for NOTORIOUS is reputable.
Detailed Comparison
Let's compare the meanings more directly:
NOTORIOUS: Known for bad things (bad fame).
infamous: Known for bad things (bad fame) - Synonym.
vicious: Cruel or violent - Related negative trait, not an antonym of 'known for bad things'.
reputable: Having a good reputation, respected - Known for good things (good fame or esteem). This is the opposite.
disgraceful: Causing shame - Describes a quality, not the state of being known for it, and not the opposite of being known for bad things.
The word reputable stands out as the word that means having a good reputation, directly opposing the meaning of notorious which means having a bad reputation.
Revision Table: Vocabulary Building
Word
Meaning
Type
Example Sentence
NOTORIOUS
Famous or well-known for something bad.
Adjective
He is a notorious thief in the city.
infamous
Well known for being bad or wicked.
Adjective
The building is infamous for its haunted history.
vicious
Cruel or violent; deliberately hurtful.
Adjective
He received a vicious bite from the guard dog.
reputable
Having a good reputation; respected.
Adjective
They hired a reputable company to handle the repairs.
disgraceful
Shockingly bad; bringing shame or disapproval.
Adjective
His behaviour at the party was absolutely disgraceful.
Additional Information on Antonyms and Synonyms
Understanding antonyms and synonyms is crucial for expanding vocabulary and improving language skills. Antonyms are words with opposite meanings, while synonyms are words with similar meanings.
Identifying antonyms often involves thinking about the core concept of a word and finding a word that negates or reverses that concept. For notorious (known for bad), the opposite is being known for good, which is captured by reputable (known for good).
Sometimes, a word might have multiple antonyms depending on the specific context. However, in multiple-choice questions, we look for the most direct and appropriate opposite among the given options.
Synonyms help in using varied language and avoiding repetition. For instance, 'infamous' is a synonym for 'notorious'.
Building a strong vocabulary involves learning not just the definitions of words, but also their relationships with other words (synonyms, antonyms, related terms).
Paper & answer key PDF ↗ Question 78archived
Select the most appropriate option to fill in the blank.
Charles Dickens was different in his style of writing from most of his ______ in the Victorian era.
- A
contemporaries
- B
critics
- C
confidants
- D
cronies
Show answer
A. contemporariesUnderstanding Dickens' Writing Style Compared to Victorian Contemporaries
This question asks us to identify the group of people during the Victorian era whose writing styles were different from that of the renowned author Charles Dickens.
Charles Dickens' Unique Literary Position
Charles Dickens is one of the most famous novelists of the 19th century, a period known as the Victorian era. His writing style was characterized by detailed descriptions, memorable characters, social criticism, humor, and often a sentimental tone. The question implies that Dickens possessed a distinct literary approach compared to others in his profession during the same time period.
Analyzing the Options for Victorian Writers
Let's examine the meaning of each option to find the best fit:
Contemporaries: This term refers to people who live or exist at the same time as someone else. In the context of literature, contemporaries are writers who were active during the same historical period. Charles Dickens certainly had many literary contemporaries in the Victorian era, such as William Makepeace Thackeray, George Eliot, and the Brontë sisters. His unique narrative techniques and focus on social issues often made his style stand out from theirs. Therefore, this word fits the context perfectly, suggesting Dickens was stylistically different from his fellow writers of the time.
Critics: Literary critics are individuals who analyze, interpret, and evaluate works of literature. While Dickens's work was certainly subject to criticism, the sentence structure suggests a comparison with peers or fellow writers, not those who reviewed his work. Dickens's style might have been differently received by critics, but he wasn't stylistically different *from* the critics themselves.
Confidants: A confidant is a person with whom one shares secrets or private affairs. This relates to personal relationships, not professional or literary comparisons. Dickens's writing style was not different from his confidants in a professional sense.
Cronies: Cronies are close friends, often implying a shared lifestyle or activities. Similar to confidants, this term refers to personal associations rather than professional contemporaries in the literary world. It doesn't fit the context of comparing writing styles within a professional field.
Conclusion on Dickens's Victorian Peers
Based on the definitions, the word that best describes the group of writers from the Victorian era whose writing style was different from Charles Dickens is contemporaries. Dickens's distinctive voice and thematic concerns set him apart from many of his fellow novelists working during that same prolific period.
Key Terminology
Term
Meaning in Context
Contemporaries
Writers living and working during the same period (Victorian era).
Critics
Individuals who evaluate literary works.
Confidants
Close friends privy to personal matters.
Cronies
Close companions or friends.
Therefore, the most appropriate choice is the first option.
Paper & answer key PDF ↗ Question 79archived
Select the option that can be used as a one-word substitute for the given group of words/phrases.
One who is indifferent to art and culture
- A
philistine
- B
philanderer
- C
scientist
- D
cynic
Show answer
A. philistineUnderstanding the Question: One-Word Substitute for Indifference to Art and Culture
The question asks for a single word that describes a person who is uninterested in or even hostile towards art and culture. We need to examine the provided options and find the one that best fits this description.
Analyzing the Options
Let's look at the meaning of each option provided:
philistine: This term refers to a person who is hostile or indifferent to culture and the arts, or who has no understanding of them.
philanderer: This word describes a man who readily engages in casual sexual encounters; a womanizer.
scientist: A scientist is a person who studies or has a specialized knowledge of one or more of the natural or physical sciences.
cynic: A cynic is a person who believes that people are motivated purely by self-interest rather than acting for honorable or unselfish reasons.
Finding the Correct One-Word Substitute
We are looking for a word that means "one who is indifferent to art and culture". Comparing this definition with the meanings of the options:
A 'philanderer' is related to romantic relationships, not art and culture.
A 'scientist' studies science, which is different from being indifferent to art and culture (a scientist could also be interested in art and culture).
A 'cynic' has a particular view on human motivation, which is unrelated to their interest in art and culture.
A 'philistine' directly matches the definition of someone hostile or indifferent to art and culture.
Therefore, the word 'philistine' is the correct one-word substitute for the phrase "One who is indifferent to art and culture".
Conclusion
Based on the analysis of the options, the word that precisely means someone indifferent to art and culture is 'philistine'.
Revision Table: Understanding Vocabulary
Word
Meaning
Relevance to "Indifferent to Art and Culture"
Philistine
Indifferent or hostile to art and culture
Direct match
Philanderer
Womanizer (casual sexual encounters)
Not relevant
Scientist
Expert in science
Not directly relevant
Cynic
Believes in self-interest motivation
Not relevant
Additional Information: Expanding Vocabulary
Learning one-word substitutes is important for improving vocabulary and communication efficiency. Here are a few related points:
Nuance: Different words might have slightly different connotations. 'Philistine' often implies a lack of appreciation or even hostility, not just simple lack of interest.
Context: The best word choice often depends on the specific context of the sentence or situation.
Etymology: The word 'philistine' comes from the Philistines, an ancient people who were traditional enemies of the Israelites in the Bible. The term was later used in Germany to refer to townspeople who were not university students, contrasting them with the cultured student body, eventually evolving to its current meaning regarding indifference to culture.
Paper & answer key PDF ↗ Question 80archived
Select the most appropriate option to substitute the underlined segment in the given sentence. If no substitution is required, select No improvement.
Though many European t raders visit Puducherry in the sixteenth century onwards , what remains today is a relic of its French past.
- A
trader visit Puducherry from the sixteenth century onwards
- B
No improvement
- C
traders visited Puducherry in a sixteenth century onward
- D
traders visited Puducherry from the sixteenth century onwards
Show answer
D. traders visited Puducherry from the sixteenth century onwardsAnalysing the Sentence for Grammar Improvement
The original sentence provided is: "Though many European t raders visit Puducherry in the sixteenth century onwards, what remains today is a relic of its French past." We need to look at the underlined segment: "t raders visit Puducherry in the sixteenth century onwards" and determine if it requires substitution for better grammar and clarity.
Identifying Issues in the Original Segment
Spelling: "t raders" is incorrectly spelled. It should be "traders".
Verb Tense: The phrase "sixteenth century onwards" indicates a past period of activity that started in the past and continued. The consequence is described using the present tense ("what remains today"), but the action of traders visiting happened in the past. Therefore, the verb "visit" should be in the simple past tense, which is "visited".
Preposition and Phrase: The phrase "in the sixteenth century onwards" is less common and slightly awkward. When specifying a starting point in time followed by "onwards," the preposition "from" is standard and more appropriate. Thus, "from the sixteenth century onwards" is preferred.
Based on these points, the underlined segment requires improvement.
Evaluating the Substitution Options
Let's examine each option provided:
trader visit Puducherry from the sixteenth century onwards
This option corrects the preposition to "from" and uses "onwards" correctly. However, it uses "trader" (singular) instead of "traders" (plural, required because of "many European traders") and keeps the incorrect present tense verb "visit" instead of "visited". Thus, this option is incorrect.
No improvement
As we identified multiple issues with the original segment (spelling, verb tense, preposition), no improvement is not the correct choice.
traders visited Puducherry in a sixteenth century onward
This option corrects the subject to the plural "traders" and the verb to the past tense "visited". However, it uses "in a sixteenth century" which is grammatically incorrect; it should be "in the sixteenth century" or, preferably in this context, "from the sixteenth century". Also, it uses "onward" instead of the plural "onwards" which is typically used when referring to time from a specific point. Thus, this option is incorrect.
traders visited Puducherry from the sixteenth century onwards
This option corrects the spelling to "traders" (plural), uses the correct past tense verb "visited", and uses the appropriate preposition and phrase "from the sixteenth century onwards". This option addresses all the identified issues in the original segment.
Concluding the Most Appropriate Option
Comparing the original sentence segment with the provided options, option 4 corrects all the grammatical errors and awkward phrasing present in the original sentence segment.
Original Segment
Issues
t raders visit Puducherry in the sixteenth century onwards
Spelling (t raders), Verb Tense (visit), Preposition (in the... onwards)
Option
Analysis
1. trader visit Puducherry from the sixteenth century onwards
Incorrect (singular 'trader', present 'visit')
2. No improvement
Incorrect (original segment has errors)
3. traders visited Puducherry in a sixteenth century onward
Incorrect (awkward 'in a sixteenth century', singular 'onward')
4. traders visited Puducherry from the sixteenth century onwards
Correct (plural 'traders', past 'visited', 'from... onwards')
Therefore, the most appropriate option to substitute the underlined segment is "traders visited Puducherry from the sixteenth century onwards".
Revision Table: Key Grammar Concepts
Concept
Explanation
Example
Subject-Verb Agreement
A plural subject requires a plural verb (in simple present/past tenses, except for 'be'). 'Many traders' is plural, so the verb should agree.
One trader visits. Many traders visit.
One trader visited. Many traders visited.
Past Tense
Used to describe actions completed in the past. The context "sixteenth century onwards" indicates a period in the past, requiring a past tense verb.
They visit (present). They visited (past).
Preposition with Time (from... onwards)
"From [time/point] onwards" is used to indicate a starting point in time from which something continues.
From 1990 onwards, the population grew.
Meetings will be held from Monday onwards.
Additional Information: Understanding 'Onward' vs. 'Onwards'
Both 'onward' and 'onwards' function as adverbs meaning "forward" or "continuing from a particular point".
Onward: Often used as an adjective (e.g., "the onward journey") or in American English as an adverb.
Onwards: More commonly used as an adverb, especially in British English, and frequently follows the structure "from [point] onwards" when referring to time or place.
In the context of "from the sixteenth century...", 'onwards' is the standard and more appropriate choice.
Paper & answer key PDF ↗ Question 81archived
Select the most appropriate meaning of the underlined idiom in the given sentence.
The loyal watchman wascut to the quickwhen he was accused of theft.
- A
dismissed
- B
imprisoned
- C
severely punished
- D
hurt intensely
Show answer
D. hurt intenselyUnderstanding the Idiom: Cut to the Quick
The question asks for the meaning of the underlined idiom "cut to the quick" in the sentence: "The loyal watchman was cut to the quick when he was accused of theft."
Idioms are phrases whose meaning cannot be deduced from the literal meaning of the individual words. "Cut to the quick" is a common English idiom.
What does "Cut to the Quick" Mean?
The idiom "cut to the quick" means to hurt someone's feelings deeply, intensely, or severely. The word "quick" in this context refers to the living flesh beneath the skin or fingernails, a particularly sensitive area. To be 'cut to the quick' is to be wounded in the most sensitive part, metaphorically referring to emotional or psychological pain.
Analyzing the Sentence Context
In the given sentence, the watchman is described as "loyal". When this loyal person is accused of theft, an act contrary to their character and duty, the accusation is likely to cause intense emotional pain. Being falsely accused, especially when loyal, can feel like a deep personal attack.
Therefore, the phrase "cut to the quick" describes the intense emotional impact of the false accusation on the loyal watchman.
Evaluating the Options
Let's look at the provided options and see which one best matches the meaning of "cut to the quick" in this context:
dismissed: This means being fired from a job. While an accusation of theft could lead to dismissal, "cut to the quick" describes the emotional reaction, not the consequence of losing the job.
imprisoned: This means being put in jail. This is a legal consequence of a crime, not the emotional feeling caused by an accusation.
severely punished: This refers to harsh consequences or penalties. Like dismissal or imprisonment, punishment is a potential outcome of an accusation, not the feeling of being deeply hurt by it.
hurt intensely: This directly describes a feeling of deep emotional pain. Being "cut to the quick" is exactly about being wounded emotionally in a profound way.
Conclusion
Comparing the meaning of the idiom "cut to the quick" with the options, "hurt intensely" is the most accurate description of the emotional state the watchman experienced upon being falsely accused of theft.
Revision Table: Idiom Meaning
Idiom
Meaning
Contextual Example
Cut to the quick
To hurt someone's feelings deeply; to wound intensely (emotionally or psychologically)
Being accused of lying cut him to the quick.
Additional Information: Understanding Idioms
Understanding idioms is crucial for comprehending spoken and written English. Idioms add color and depth to language, but their meanings must be learned, as they are not literal. When encountering an unfamiliar idiom, try to understand it from the context of the sentence, or look up its established meaning. Other idioms related to emotional reactions include "stew in your own juice" (to suffer the consequences of one's actions), "have a chip on your shoulder" (to hold a grudge or grievance), or "wear your heart on your sleeve" (to openly show emotions).
Paper & answer key PDF ↗ Question 82archived
Select the most appropriate option to fill in blank No.1.
- A
initial
- B
antique
- C
extinct
- D
ancient
Show answer
D. ancientThe question asks us to fill in the blanks in the given passage using the most appropriate options. We need to select the best word for each blank based on the context of the sentence and the overall meaning of the passage.
Analyzing Blank No. 1 in the Passage
The first sentence of the passage is: "Perhaps India should listen to her (1)______ sages who taught the importance (2)______ balance." We are asked to choose the most appropriate word for blank (1) from the given options: initial, antique, extinct, or ancient. The word immediately following the blank is "sages". Sages are wise individuals, often associated with wisdom or knowledge from the past.
Evaluating Options for Blank No. 1
Let's look at each option and see how it fits with the word "sages":
Initial: This means existing or occurring at the beginning. While sages might have been present at the beginning of something (like a tradition), calling them "initial sages" doesn't strongly connect with the idea of their enduring wisdom being relevant today.
Antique: This term is typically used for objects or furniture from an earlier period, valued for their age or historical significance. It is not commonly used to describe people, especially wise teachers like sages.
Extinct: This means no longer in existence. If the sages were extinct, it would mean they no longer exist, which doesn't make sense in the context of listening to their teachings today.
Ancient: This refers to belonging to the very distant past. "Ancient sages" fits perfectly with the idea of wise teachers from history whose teachings are still relevant. The passage suggests listening to these sages, implying their wisdom has been passed down through time from antiquity.
Determining the Most Appropriate Word
Considering the meaning of "sages" as wise people from the past and the context of listening to their teachings for guidance today, the word that best describes them is "ancient". "Ancient sages" conveys the idea of wise individuals who lived in the distant past and whose wisdom continues to be valuable.
Comparison of Options for Blank 1
Option
Meaning
Fit with "sages" in context
Initial
Existing at the beginning
Doesn't emphasize historical depth or enduring wisdom.
Antique
Object from an earlier period
Not used for people.
Extinct
No longer in existence
Contradicts the idea of listening to them today.
Ancient
Belonging to the distant past
Fits perfectly with wise teachers from history whose teachings are relevant.
Based on this analysis, "ancient" is clearly the most appropriate option to fill blank No. 1.
Revision Table: Understanding Key Terms
Term
Meaning in Context
Sages
Wise teachers or individuals, often associated with ancient wisdom.
Passage
A short section of a text.
Appropriate
Suitable or fitting for a particular purpose or occasion.
Alternatives
Other options or choices available.
Additional Information: The Importance of Context
When filling blanks in a passage, understanding the context is crucial. The words surrounding the blank, the overall theme of the passage, and the options provided all help in determining the most appropriate word. In this case, the word "sages" strongly suggests a term related to historical period or origin. The idea of "listening" to them implies their wisdom is still accessible and relevant, ruling out terms like "extinct". The options must be evaluated based on their meaning and how well they fit grammatically and contextually into the sentence.
Paper & answer key PDF ↗ Question 83archived
Select the option that can be used as a one-word substitute for the given group of words/phrases.
One who embraces voluntary death for the sake of one's country
- A
martyr
- B
fanatic
- C
patriot
- D
diplomat
Show answer
A. martyrUnderstanding Voluntary Death for Country
The question asks for a single word that describes someone who willingly gives up their life for the benefit or cause of their country. This is a significant sacrifice made out of deep loyalty and love for one's nation.
Analyzing the Options
Let's look at the provided options and see which one best fits the description:
martyr: A martyr is typically defined as a person who is killed because of their religious or other beliefs, or who suffers greatly or dies for a cause. Dying voluntarily for one's country is certainly a cause, making this option a strong possibility.
fanatic: A fanatic is someone with extreme and single-minded zeal for a particular cause, usually a political or religious one. While a fanatic might be dedicated to their country, the word itself doesn't specifically mean they die for it.
patriot: A patriot is a person who strongly supports their country and is prepared to defend it. A patriot has deep love for their country and might risk their life, but the term "patriot" doesn't inherently mean they have embraced voluntary death.
diplomat: A diplomat is an official who represents a country in its relations with other countries. This role is related to international relations, not typically to dying for one's country.
Selecting the Correct Word Substitute
Comparing the options, the word that most accurately captures the meaning of "One who embraces voluntary death for the sake of one's country" is "martyr". While a patriot loves and defends their country, a martyr is someone who dies for a cause, including the cause of their nation.
Why 'martyr' is the Best Fit
The term 'martyr' directly addresses the core concept of death for a principle or cause. In the context of dying for one's country, the country's freedom, sovereignty, or safety becomes the cause for which the individual makes the ultimate sacrifice. The death is embraced voluntarily, aligning with the idea of a martyr choosing their fate for their beliefs or cause.
Therefore, martyr is the appropriate one-word substitute for the given phrase.
Revision Table: Key Term Definitions
Understanding the precise meaning of each word is crucial for selecting the correct substitute. Below is a table summarizing the key terms.
Term
Definition
Relevance to "dying for country"
Martyr
A person who dies for a cause or belief.
Directly applicable; dying for one's country is a cause.
Fanatic
A person with extreme zeal for a cause.
Implies strong dedication but not necessarily death.
Patriot
A person who supports and defends their country.
Implies love and defense, but not specifically voluntary death.
Diplomat
An official representing a country abroad.
Unrelated to dying for the country's cause.
Additional Information on Sacrifice for Country
The concept of making sacrifices, even the ultimate sacrifice of life, for one's country is a theme found across many cultures and histories. It is often associated with defending the nation against aggression, fighting for freedom, or upholding core national values.
While "martyr" specifically refers to someone dying for a cause, other terms relate to commitment to country:
Hero: A person admired for courage or outstanding achievements. Someone dying for their country might also be considered a national hero.
Soldier/Warrior: Individuals serving in the military who are prepared to fight and potentially die for their country as part of their duty.
The phrase "embraces voluntary death" emphasizes the intentional choice made by the individual, which aligns strongly with the definition of a martyr.
Paper & answer key PDF ↗ Question 84archived
Given below are four jumbled sentences. Select the option that gives their correct order.
A. For a split second, as the stranger stepped into the light, his furry head was clearly visible.
B. At first, all seemed still outside the house,except for the sound of the rain.
C. Recognizing him, Joe stood petrified staring at the man wearing a long coat,wet from rain.
D. But then, footsteps approached the house and a stranger emerged out of the darkness.
- A
BDAC
- B
CABD
- C
DACB
- D
BCDA
Show answer
A. BDACUnderstanding Jumbled Sentences
The question asks us to arrange four jumbled sentences (A, B, C, and D) into a coherent and logical paragraph. To do this, we need to read each sentence carefully and identify the logical flow of events or ideas.
Analyzing Each Sentence
Sentence A: For a split second, as the stranger stepped into the light, his furry head was clearly visible. (Describes a detail about the stranger after he is visible)
Sentence B: At first, all seemed still outside the house, except for the sound of the rain. (Sets the initial scene - quietness, rain)
Sentence C: Recognizing him, Joe stood petrified staring at the man wearing a long coat, wet from rain. (Describes Joe's reaction after seeing and recognizing the stranger)
Sentence D: But then, footsteps approached the house and a stranger emerged out of the darkness. (Introduces a change from the initial scene - footsteps, emergence of a stranger)
Finding the Logical Sequence
Let's consider the order of events:
We need to start with a sentence that sets the scene. Sentence B does this by describing the initial quiet environment.
Next, something needs to happen to change this scene. Sentence D introduces the arrival of footsteps and the appearance of a stranger, which follows logically from the initial quiet setting described in B. So, BD is the likely start.
After the stranger emerges (D), the next logical step is to describe something about the stranger or his appearance as he becomes visible. Sentence A describes seeing his "furry head" as he steps into the light. This fits after the stranger has emerged from darkness into light. So, BDA seems correct so far.
Finally, Sentence C describes Joe's reaction ("Recognizing him, Joe stood petrified...") upon seeing the stranger clearly. This reaction would happen after the stranger is visible and recognizable (A). So, C follows A.
This step-by-step analysis suggests the order BDAC.
Evaluating the Options
Let's check the given options against our derived sequence:
Option 1: BDAC - This matches our logical sequence.
Option 2: CABD - Starts with Joe recognizing the man (C), which cannot happen before the man appears. Incorrect.
Option 3: DACB - Starts with the stranger emerging (D) before setting the initial scene (B). Incorrect.
Option 4: BCDA - Describes Joe recognizing the man (C) right after the scene is set (B) but before the stranger appears (D). Incorrect.
Based on the logical flow and event sequence, the correct order is BDAC.
Correct Order of Sentences
The sentences arranged in the correct order are:
B. At first, all seemed still outside the house, except for the sound of the rain.
D. But then, footsteps approached the house and a stranger emerged out of the darkness.
A. For a split second, as the stranger stepped into the light, his furry head was clearly visible.
C. Recognizing him, Joe stood petrified staring at the man wearing a long coat, wet from rain.
This sequence tells a clear story, starting with a quiet scene, introducing a disturbance, describing the appearance of the source of the disturbance, and ending with a character's reaction.
Revision Table: Jumbled Sentence Skills
Skill
Description
Why it's Important
Identifying the opening sentence
Finding the sentence that introduces the topic or sets the scene.
Helps establish the context.
Identifying linking words/phrases
Words like 'but then', 'after this', 'therefore', 'as a result'.
Indicate connections and transitions between sentences.
Recognizing Pronoun/Noun relationships
Understanding which noun a pronoun (like 'him', 'he', 'it') refers to.
Ensures sentences that refer back to previously mentioned subjects are placed correctly.
Following chronological order
Arranging events in the sequence they happened.
Crucial for narrative passages.
Establishing cause and effect
Identifying sentences that describe actions and their consequences.
Important for descriptive and explanatory passages.
Additional Information: Mastering Paragraph Jumbles
Paragraph jumbles, also known as sentence reordering or para jumbles, are common in various English proficiency tests. They assess your ability to understand coherence and logical flow in writing. Here are some tips for solving them:
Read all sentences first: Get a general understanding of the topic and the different points being made.
Look for introductory sentences: These often introduce a subject or setting and don't start with conjunctions or pronouns referring to something not yet mentioned.
Identify concluding sentences: These might summarize, offer a final thought, or provide a conclusion.
Find mandatory pairs: Look for sentences that clearly must follow each other (e.g., a cause and its effect, a question and its answer, a general statement and an example). Linking words are very helpful here.
Check pronoun references: Ensure that pronouns (he, she, it, they, this, that) correctly refer back to nouns mentioned in previous sentences.
Look for transitions: Words like 'however', 'therefore', 'in addition', 'meanwhile', 'subsequently' show connections and help determine the order.
Test options: Once you have a potential order, read the sentences in that sequence to see if it forms a cohesive paragraph. If you're unsure, test out the given options.
Practicing with different types of jumbled sentences will help you develop an intuition for logical connections and sentence flow.
Paper & answer key PDF ↗ Question 85archived
Select the most appropriate option to fill in blank No.2.
- A
by
- B
of
- C
for
- D
in
Show answer
B. ofUnderstanding the Passage and Blank No. 2
The passage discusses the importance of balance, drawing a parallel with ancient Indian sages' teachings. It emphasizes avoiding extremes and the negative consequences of going too far, such as environmental degradation. We need to fill in blank No. 2, which appears in the phrase "the importance (2)______ balance". This phrase talks about what kind of importance is being referred to – the importance related to "balance".
Analyzing Options for Blank No. 2
Let's look at the provided options for blank No. 2 and see which one fits correctly in the context of the sentence:
by: Using "importance by balance" doesn't make grammatical sense in this context. "By" usually indicates the means or agent of an action.
of: The phrase "importance of balance" is a standard and correct construction in English. When we talk about the importance of something, we use the preposition "of".
for: While "importance for something" can sometimes be used (e.g., "importance for future development"), "importance of balance" is the much more common and appropriate phrasing when specifying what is important, especially in a general sense like the importance of a concept or quality.
in: "Importance in balance" doesn't fit grammatically or convey the intended meaning. "In" might be used to describe where importance lies (e.g., "There is importance in this decision"), but not after "importance" to specify the subject of that importance.
Determining the Correct Preposition
The structure "importance of + [noun]" is the standard way to express that the noun is important. For example, we say "the importance of education," "the importance of health," or "the importance of communication." In this case, the phrase is "the importance (2)______ balance." Following the standard usage, the correct preposition to connect "importance" to "balance" is "of."
Let's insert "of" into the phrase:
"the importance of balance"
This creates a grammatically sound and meaningful phrase that fits perfectly within the sentence.
Completing the Sentence with Blank No. 2 Filled
With "of" in blank No. 2, the relevant part of the sentence becomes:
"...sages who taught the importance of balance."
This sentence is grammatically correct and conveys the intended meaning that the sages taught how important balance is.
Conclusion for Blank No. 2
Based on grammatical rules and common English usage, the most appropriate option to fill in blank No. 2 is "of".
Revision Table: Blank 2 Options
Option
Fit in Sentence ("importance ______ balance")
Reasoning
by
importance by balance
Incorrect grammar, meaning unclear.
of
importance of balance
Correct standard phrase.
for
importance for balance
Less common/appropriate than "of" in this context.
in
importance in balance
Incorrect grammar, meaning unclear.
Additional Information: Using Prepositions with Nouns
Choosing the correct preposition after a noun can be tricky in English. The choice often depends on the specific noun and the context. Here are a few examples of nouns commonly followed by prepositions:
Importance: Usually followed by "of" (importance of something) or sometimes "for" (importance for someone/something, importance for a result).
Knowledge: Often followed by "of" (knowledge of a subject) or "about" (knowledge about a situation).
Difference: Can be followed by "between" (difference between two things) or "in" (difference in size).
Need: Often followed by "for" (need for help) or "of" (a need of theirs).
Learning these common noun+preposition combinations is essential for improving grammar and fluency in English, especially in questions like fill in the blanks or cloze tests.
Paper & answer key PDF ↗ Question 86archived
Select the most appropriate option to fill in the blank.
She performs different roles very convincingly as she is a very ______ actor.
- A
versatile
- B
virtuous
- C
verbose
- D
voracious
Show answer
A. versatileUnderstanding the Question: Choosing the Right Word for an Actor
The question asks us to find the most suitable word to describe an actor who is capable of performing various roles in a convincing manner. We need an adjective that reflects this ability to handle different types of characters and performances effectively.
Analyzing the Options for the Blank
Let's look at the meaning of each word provided in the options:
versatile: This word means able to adapt or be adapted to many different functions or activities. In the context of an actor, it means being skilled at playing many different types of roles.
virtuous: This word means having or showing high moral standards. It relates to a person's character or morality, not their ability to perform different acting roles.
verbose: This word means using or expressed in more words than are needed. It describes someone who talks a lot or uses too many words, typically in speech or writing. This is not related to acting skill in different roles.
voracious: This word means wanting or devouring great quantities of food, or having a very eager approach to an activity. While an actor might have a voracious appetite for learning roles, the word itself doesn't describe the ability to perform different types of roles convincingly.
Identifying the Most Appropriate Word for a Versatile Actor
The sentence describes an actor who "performs different roles very convincingly." This clearly points to someone who is skilled and adaptable across various types of performances. Out of the given options, the word that best captures this ability to excel in many different roles is "versatile".
A versatile actor can transition seamlessly from a comedic role to a dramatic one, or from playing a hero to portraying a villain, and still make each performance believable and convincing.
Let's see how the other words fit:
A virtuous actor might be a good person, but that doesn't mean they can play many different roles well.
A verbose actor might talk a lot, which isn't directly related to their ability to perform different parts convincingly.
A voracious actor might eagerly take on roles, but the word itself doesn't mean they are good at *different* roles.
Therefore, "versatile" is the only word that correctly describes an actor capable of performing different roles convincingly.
Completing the Sentence
Filling in the blank with the most appropriate word, the sentence becomes:
She performs different roles very convincingly as she is a very versatile actor.
Option
Meaning
Relevance to performing different roles convincingly
versatile
Able to adapt to many different functions/activities
Highly relevant — describes skill in various roles
virtuous
Having high moral standards
Not relevant
verbose
Using too many words
Not relevant
voracious
Eager approach; devouring large quantities
Not relevant to performing *different* roles convincingly
Revision Table: Understanding Vocabulary in Context
Word
Meaning in Simple Terms
Example Usage
Versatile
Good at doing many different things
A versatile player can play forward or defense.
Virtuous
Morally good; having strong principles
She is known for her virtuous deeds.
Verbose
Using too many words when speaking or writing
His explanation was too verbose and confusing.
Voracious
Very eager or enthusiastic about an activity; eating a lot
He is a voracious reader; she has a voracious appetite.
Additional Information: Qualities of a Skilled Actor
Beyond being versatile, a skilled actor often possesses many other qualities:
Expressiveness: The ability to convey emotions clearly.
Empathy: Understanding and sharing the feelings of others (including the character).
Discipline: Committing to rehearsals, character study, and performances.
Stage Presence: The ability to command attention when performing.
Voice and Movement Control: Using their voice and body effectively to portray the character.
Being versatile means they can apply these skills across a wide range of character types and genres, making them highly valuable in the acting profession.
Paper & answer key PDF ↗ Question 87archived
Select the most appropriate option to fill in blank No.4.
- A
but
- B
so
- C
or
- D
otherwise
Show answer
C. orUnderstanding Fill in the Blanks Questions
Fill in the blanks questions test your vocabulary and understanding of context, grammar, and sentence structure. You need to read the entire passage carefully to grasp the overall meaning and then select the most appropriate word from the given options for each blank.
Analyzing the Passage and Blank No. 4
The passage talks about India potentially learning from ancient sages about the importance of balance. It suggests avoiding extremes. The sentence relevant to blank No. 4 is:
"This means we should be (3)______ not to take anything too far (4)______ be too radical."
The phrase "not to take anything too far" describes one extreme to avoid. The phrase "be too radical" describes another extreme to avoid. The word in blank No. 4 needs to connect these two things that should be avoided.
Evaluating Options for Blank No. 4
Let's look at the given options and see how they fit into the sentence:
but: If we use "but", the sentence becomes "not to take anything too far but be too radical." "But" usually introduces a contrast or something unexpected. Here, "be too radical" is not a contrast to "not taking things too far"; they are both extremes to avoid. So, "but" doesn't fit the meaning.
so: If we use "so", the sentence becomes "not to take anything too far so be too radical." "So" indicates a result or consequence. Avoiding taking things too far doesn't result in being too radical. This doesn't make sense in the context.
or: If we use "or", the sentence becomes "not to take anything too far or be too radical." This means we should avoid taking things too far, AND we should also avoid being too radical. "Or" is used here to connect two negative possibilities that should both be avoided. This fits the meaning perfectly.
otherwise: If we use "otherwise", the sentence becomes "not to take anything too far otherwise be too radical." "Otherwise" means "if not." This implies that if you don't take things too far, the consequence will be being too radical, which is illogical in this context.
Determining the Most Appropriate Option
Comparing the options, "or" is the only word that correctly connects the two phrases indicating things to be avoided ("not to take anything too far" and "be too radical"). The sentence advises against either extreme.
Final Answer for Blank No. 4
Based on the analysis, the most appropriate option to fill in blank No. 4 is "or".
Blank No.
Phrase Context
Most Appropriate Option
Reasoning
4
...not to take anything too far (4)______ be too radical.
or
Connects two alternative extremes to avoid.
Revision Table: Important Conjunctions for Fill in Blanks
Conjunction
Common Usage
Example
And
Connects items, ideas, or clauses that are similar or additional.
He is kind and generous.
But
Connects contrasting ideas or clauses.
She is smart, but she is lazy.
Or
Connects alternatives or choices; connects negative possibilities to avoid.
Would you like tea or coffee? Don't run or jump inside.
So
Indicates result or consequence.
It was raining, so I took an umbrella.
Otherwise
Indicates a consequence if something is not done.
Study hard, otherwise you will fail.
Additional Information: Contextual Vocabulary for Passages
When tackling fill-in-the-blanks passages, understanding the surrounding words and the overall theme is crucial. Words like "sages," "importance," "balance," "radical," and "environmental degradation" provide clues about the passage's topic – likely related to philosophy, moderation, and consequences of extreme actions.
Paying attention to:
The tone of the passage (e.g., cautionary, informative, philosophical).
Grammatical structure (e.g., prepositions, conjunctions, verb forms needed).
Words that indicate cause and effect, contrast, addition, or alternatives.
helps in choosing the most appropriate word for each blank, ensuring the completed passage is grammatically correct and logically sound.
Paper & answer key PDF ↗ Question 88archived
Select the most appropriate meaning of the underlined idiom in the given sentence.
It is unfortunate that most people in the country are still living from hand to mouth .
- A
saving for the future generations
- B
earning wealth by selfish means
- C
doing manual labour
- D
consuming daily what little is earned
Show answer
D. consuming daily what little is earnedUnderstanding the Idiom: Living From Hand to Mouth
The question asks for the most appropriate meaning of the underlined idiom, "living from hand to mouth," as used in the sentence: "It is unfortunate that most people in the country are still living from hand to mouth."
An idiom is a phrase or expression whose meaning cannot be deduced from the literal meaning of the words in it. The idiom "living from hand to mouth" describes a particular financial situation.
Meaning of "Living From Hand to Mouth"
The idiom "living from hand to mouth" means having just enough money to live on and nothing extra. It implies that whatever little money is earned is immediately spent on basic daily necessities like food and shelter, with no possibility of saving or planning for the future. People living from hand to mouth struggle to make ends meet on a daily basis.
Analyzing the Sentence and Options
The sentence states that "most people in the country are still living from hand to mouth." This suggests a widespread condition of financial hardship among the population, where income is just sufficient for immediate survival.
Let's evaluate the given options based on the meaning of the idiom:
Option 1: saving for the future generations
This option suggests having enough extra money not only for future savings but even for future generations. This is the opposite of living from hand to mouth, which involves spending all income on immediate needs.
Option 2: earning wealth by selfish means
This option describes the method of earning money (selfish means) and the outcome (earning wealth). The idiom "living from hand to mouth" refers to the state of having very little money for daily needs, regardless of how it was earned or whether wealth is accumulated. This option is irrelevant to the idiom's meaning.
Option 3: doing manual labour
This option describes a type of work. While people who do manual labour might sometimes live from hand to mouth, the idiom itself does not define the type of work done. It describes a financial state, not an occupation.
Option 4: consuming daily what little is earned
This option perfectly captures the essence of "living from hand to mouth." It means that the small amount of money earned each day or period is immediately used up for consumption (daily needs), leaving nothing left. This directly corresponds to the idea of having just enough for immediate survival without any surplus.
Conclusion on the Most Appropriate Meaning
Comparing the options with the established meaning of "living from hand to mouth," option 4 is the only one that accurately describes the financial situation implied by the idiom. It reflects the lack of savings and the immediate consumption of meagre earnings for daily survival.
Revision Table: Understanding Idioms
Idiom
Approximate Meaning
Example Usage
Living from hand to mouth
Having just enough money for basic daily needs with nothing left over.
Many families in rural areas are living from hand to mouth.
A drop in the ocean
A very small part of something much larger.
Our donation was a drop in the ocean compared to the total needed.
Break a leg
Good luck (used to wish someone luck, especially before a performance).
You have a big audition tomorrow? Break a leg!
Additional Information: The Importance of Idioms in English
Idioms are an integral part of the English language. Understanding them is crucial for comprehending native speakers and reading authentic texts. They add color and nuance to communication.
Idioms often have cultural origins.
Their meanings are figurative, not literal.
Learning common idioms improves fluency and comprehension.
Using idioms appropriately can make your English sound more natural.
Regularly encountering and trying to understand idioms in context is a good way to learn them.
Paper & answer key PDF ↗ Question 89archived
In the sentence identify the segment which contains the grammatical error.
Most disputes can be solved amicably unless one are rigid.
- A
Most disputes
- B
unless one are
- C
rigid
- D
can be solved amicably
Show answer
B. unless one areIdentifying Grammatical Errors in Sentences
The question asks us to identify the segment in the given sentence that contains a grammatical error. The sentence is: "Most disputes can be solved amicably unless one are rigid."
Analyzing the Sentence Structure
Let's break down the sentence and examine its parts to find any potential errors, focusing on grammar rules.
"Most disputes": This is the subject of the main clause. "Disputes" is a plural noun, and "Most" is a quantifier modifying it.
"can be solved amicably": This is the verb phrase and adverbial phrase modifying the subject "disputes". "can be solved" is a passive construction.
"unless one are rigid": This is a subordinate clause introduced by the conjunction "unless".
Pinpointing the Grammatical Error
We need to carefully look at the subordinate clause: "unless one are rigid."
In this clause:
The subject is "one".
The verb is "are".
"rigid" is an adjective describing "one".
The subject "one" is generally treated as a singular indefinite pronoun. According to subject-verb agreement rules, a singular subject requires a singular verb.
The verb "are" is a plural form of the verb 'to be'. It should be used with plural subjects (e.g., "they are", "we are", "disputes are").
Since the subject "one" is singular, the correct verb form should be "is".
Therefore, the segment "one are" contains the grammatical error. It should be "one is".
Correcting the Sentence
The corrected sentence would be: "Most disputes can be solved amicably unless one is rigid."
Explanation of the Grammatical Error: Subject-Verb Agreement
The error identified is a classic case of subject-verb agreement failure. Here's the rule:
A verb must agree in number (singular or plural) with its subject.
If the subject is singular, the verb must be singular.
If the subject is plural, the verb must be plural.
In the segment "unless one are rigid", the subject is "one". "One" functions here as a singular indefinite pronoun, referring to a single, unspecified person. As a singular subject, it requires the singular form of the verb 'to be', which is "is". The use of the plural verb "are" violates the subject-verb agreement rule.
Subject Type
Example Subject
Correct Verb Form (to be)
Singular Indefinite Pronoun
one
is
Plural Noun
disputes
are
Comparing the options provided:
<p>Most disputes</p> - This segment is grammatically correct. "Most disputes" is a valid plural subject phrase.
<p>unless one are</p> - This segment contains the error. "one" is singular, but "are" is plural.
<p>rigid</p> - This segment is grammatically correct. "rigid" is an adjective modifying "one".
<p>can be solved amicably</p> - This segment is grammatically correct. "can be solved" agrees with the plural subject "Most disputes".
Therefore, the segment containing the grammatical error is "unless one are".
Revision Table: Common Grammatical Errors
Error Type
Description
Example (Incorrect)
Correction
Subject-Verb Agreement
Subject and verb do not match in number (singular/plural).
The dogs is barking.
The dogs are barking.
Pronoun Agreement
Pronoun does not agree with its antecedent in number, gender, or person.
Each student must bring their book.
Each student must bring his or her book. (Or rephrase: Students must bring their books.)
Tense Consistency
Shifting tenses unnecessarily within a sentence or paragraph.
She walked to the park and sees a bird.
She walked to the park and saw a bird.
Additional Information: Indefinite Pronouns and Agreement
Indefinite pronouns refer to a non-specific person or thing. Their agreement with verbs can be tricky.
Singular Indefinite Pronouns: anybody, anyone, anything, each, either, everybody, everyone, everything, neither, nobody, no one, nothing, one, somebody, someone, something. These usually take a singular verb.
Example: Everyone is here. Nothing makes sense. One has to be careful.
Plural Indefinite Pronouns: both, few, many, several. These take a plural verb.
Example: Both are correct. Many were invited.
Indefinite Pronouns that can be Singular or Plural: all, any, most, none, some. Their number depends on the noun they refer to (if there is one) or whether they refer to something countable or uncountable.
Example: Some of the water is gone (uncountable, singular). Some of the students are gone (countable, plural).
In the given sentence, "one" is used as a singular indefinite pronoun, hence requiring the singular verb "is". Understanding these rules helps in avoiding common grammatical errors.
Paper & answer key PDF ↗ Question 90archived
Select the most appropriate option to substitute the underlined segment in the given sentence. If no substitution is required, select No improvement.
The India consensus study highlight a benefits by addin g domestic violence prevention approaches to current government policy
- A
highlight a benefit in addition
- B
No improvement
- C
highlights the benefits of adding
- D
highlight the benefits from added
Show answer
C. highlights the benefits of addingUnderstanding Sentence Improvement and Grammar
The question asks us to select the most appropriate option to replace the underlined part in the sentence:
The India consensus study highlight a benefits by addin g domestic violence prevention approaches to current government policy.
Let's analyze the underlined segment and the original sentence to identify the grammatical issues.
The subject of the sentence is "The India consensus study", which is singular. The verb "highlight" is plural. This is a subject-verb agreement error.
"a benefits" is incorrect. "Benefits" is a plural noun. We cannot use the singular indefinite article "a" before a plural noun. Also, the context suggests specific benefits are being referred to, making "the benefits" more appropriate than just "benefits" (which would imply benefits in general without specific focus).
"addin g" is a misspelling of "adding".
The phrase "by adding" implies the means by which the benefits are achieved. However, when discussing benefits that result from or are associated with something, the preposition "of" followed by the gerund is usually more fitting, i.e., "benefits of adding".
Now let's examine the given options:
Option 1: highlight a benefit in addition
"highlight" is plural, but the subject "study" is singular. Incorrect subject-verb agreement.
"a benefit" is singular, but the original sentence and the context suggest plural benefits.
"in addition" changes the meaning and structure compared to discussing benefits resulting from "adding" approaches.
Option 2: No improvement
As identified above, the original sentence has several grammatical errors (subject-verb agreement, article with plural noun, misspelling, incorrect preposition). Therefore, improvement is required.
Option 3: highlights the benefits of adding
"highlights" is singular, agreeing with the singular subject "study". Correct subject-verb agreement.
"the benefits" correctly uses the definite article with the plural noun, fitting the context.
"of adding" correctly uses the preposition "of" with the gerund "adding" to indicate the benefits associated with adding the approaches. The spelling of "adding" is also correct.
Option 4: highlight the benefits from added
"highlight" is plural, but the subject "study" is singular. Incorrect subject-verb agreement.
"the benefits" is correct.
"from added" uses the past participle "added". While grammatically possible in some contexts, "of adding" (referring to the action of adding) is more precise and commonly used in this construction to describe the benefits resulting from the action or inclusion of something.
Comparing the options, Option 3 correctly addresses all the identified grammatical errors in the original sentence and provides the most appropriate phrasing.
The corrected sentence is:
The India consensus study highlights the benefits of adding domestic violence prevention approaches to current government policy.
Analyzing Sentence Structure and Agreement
This question primarily tests understanding of:
Subject-Verb Agreement: Singular subjects take singular verbs; plural subjects take plural verbs.
Noun-Article Agreement: Using appropriate articles (a, an, the) with singular and plural countable/uncountable nouns.
Correct Preposition Usage: Selecting the correct preposition to connect ideas logically.
Correct Verb Form: Using gerunds (verb + -ing) appropriately after certain prepositions or in certain sentence structures.
Comparison of Options
Issue
Original
Option 1
Option 2
Option 3
Option 4
Subject-Verb Agreement (Study / Highlight)
Incorrect (singular subject, plural verb)
Incorrect (singular subject, plural verb)
Incorrect (original)
Correct (singular subject, singular verb)
Incorrect (singular subject, plural verb)
Article/Noun (a benefits / the benefits)
Incorrect (a + plural)
Incorrect (a + singular when plural expected)
Incorrect (original)
Correct (the + plural)
Correct (the + plural)
Preposition + Verb Form (by adding / of adding)
Incorrect (by + misspelled gerund)
Changes meaning
Incorrect (original)
Correct (of + gerund)
Incorrect (from + past participle less suitable)
Based on the analysis, Option 3 is the only one that corrects all grammatical errors and provides a coherent and grammatically sound sentence.
Revision Table: Key Grammar Concepts
Grammar Concepts for Sentence Improvement
Concept
Explanation
Example
Subject-Verb Agreement
The verb in a sentence must agree in number (singular/plural) with its subject. Add 's' or 'es' to the base form of most verbs for singular subjects in the simple present tense (except 'I' and 'you').
Singular: The dog barks. The student studies.
Plural: The dogs bark. The students study.
Articles (a, an, the)
'a' and 'an' are indefinite articles used with singular countable nouns. 'a' is used before a consonant sound, 'an' before a vowel sound.
'the' is the definite article used with specific singular or plural countable/uncountable nouns.
Indefinite: a cat, an apple
Definite: the cat on the mat, the apples in the basket
Prepositions + Gerunds
Prepositions (like of, by, from, in, on) are often followed by a gerund (the -ing form of a verb used as a noun) when the next word is a verb describing an action.
Thank you for helping me.
He is good at swimming.
Additional Information: Common Errors in Sentence Correction
Sentence correction questions often test common grammatical errors. Being aware of these can help identify issues quickly.
Tense Errors: Incorrect use of past, present, future, or perfect tenses.
Pronoun Errors: Agreement in number and gender, clarity of reference.
Modifier Errors: Misplaced or dangling modifiers that confuse the meaning.
Parallelism: Listing items or phrases without consistent grammatical structure.
Idiomatic Errors: Incorrect use of standard English phrases or preposition combinations.
Focusing on the core structure – subject, verb, object – and checking for agreement and correct word forms is crucial for sentence improvement questions.
Paper & answer key PDF ↗ Question 91archived
Select the correct active form of the given sentence.
She was seen sitting in the last row.
- A
We have seen her sitting in the last row.
- B
We saw her sitting in the last row.
- C
We see her sitting in the last row.
- D
We had seen her sitting in the last row.
Show answer
B. We saw her sitting in the last row.Understanding Voice: Active and Passive Sentences
Sentences in English can be expressed in either active voice or passive voice. The voice of a verb tells whether the subject of the sentence performs or receives the action.
Active Voice: The subject performs the action. Structure is typically Subject + Verb + Object. Example: We saw her.
Passive Voice: The subject receives the action. The doer of the action is often mentioned using "by" or is not mentioned at all if it's unknown or unimportant. Structure is typically Subject + be verb (is, am, are, was, were, etc.) + Past Participle of the verb + (by agent). Example: She was seen (by us).
The question asks us to convert a passive voice sentence into its active form.
Analyzing the Passive Sentence
The given sentence is: "She was seen sitting in the last row."
Let's break down this passive sentence:
Subject: She (She is the one who received the action of being seen).
Verb Phrase: was seen (This is the passive form of the verb 'see' in the past simple tense).
Additional Information: sitting in the last row (This phrase describes the state or position of 'She' when the action occurred).
In this passive sentence, the doer of the action (who saw her) is not explicitly mentioned. However, the options provided suggest that "We" is the likely agent.
Converting from Passive to Active Voice
To convert a passive sentence to an active sentence, we need to:
Identify the agent (the doer of the action). From the options, we can infer the agent is "We".
Make the agent the subject of the active sentence. So, the active sentence will start with "We".
Change the passive verb form back to its active form. The passive verb "was seen" is in the Past Simple tense. The active verb in the Past Simple tense is the simple past form of 'see', which is "saw".
Make the original passive subject ("She") the object of the active sentence. The object form of "She" is "her".
Keep any additional phrases or information. The phrase "sitting in the last row" remains the same.
Putting it together:
Active Subject: We
Active Verb (Past Simple): saw
Active Object: her
Rest of the sentence: sitting in the last row
The resulting active sentence is: "We saw her sitting in the last row."
Evaluating the Options
Let's examine each option based on our conversion process:
We have seen her sitting in the last row. (Verb: have seen - This is Present Perfect tense, not Past Simple). This does not match the original passive tense.
We saw her sitting in the last row. (Verb: saw - This is Past Simple tense). This matches the Past Simple tense of the original passive verb ("was seen") and the structure derived.
We see her sitting in the last row. (Verb: see - This is Present Simple tense, not Past Simple). This does not match the original passive tense.
We had seen her sitting in the last row. (Verb: had seen - This is Past Perfect tense, not Past Simple). This does not match the original passive tense.
Only option 2 uses the correct tense (Past Simple) and structure to convert the passive sentence "She was seen sitting in the last row" back to its active form with "We" as the subject.
Conclusion on Active Voice Conversion
Based on the analysis, the correct active form of the sentence "She was seen sitting in the last row" is "We saw her sitting in the last row". The conversion requires identifying the implied subject and ensuring the tense of the verb remains consistent (Past Simple in this case).
Passive Sentence Element
Active Sentence Element
Example Conversion
Subject (receives action)
Object (receives action)
She → her
Passive Verb (be + Past Participle, matches original tense)
Active Verb (original tense)
was seen (Past Simple Passive) → saw (Past Simple Active)
(by + Agent) - often implied
Subject (performs action)
(by us) → We
Revision Table: Voice Conversion Basics
Tense
Passive Voice Structure
Active Voice Structure
Example (Passive → Active)
Present Simple
is/am/are + Past Participle
Subject + Verb (base form or +s/es) + Object
The letter is written by him. → He writes the letter.
Past Simple
was/were + Past Participle
Subject + Verb (past form) + Object
She was seen by us. → We saw her.
Present Continuous
is/am/are + being + Past Participle
Subject + is/am/are + Verb(-ing) + Object
A house is being built by them. → They are building a house.
Past Continuous
was/were + being + Past Participle
Subject + was/were + Verb(-ing) + Object
The song was being sung by Mary. → Mary was singing the song.
Present Perfect
has/have + been + Past Participle
Subject + has/have + Past Participle + Object
The work has been finished by me. → I have finished the work.
Past Perfect
had + been + Past Participle
Subject + had + Past Participle + Object
The cake had been eaten by him. → He had eaten the cake.
Additional Information on Active vs. Passive Voice
Both active and passive voices are grammatically correct, but they serve different purposes. Active voice is generally preferred in writing because it is usually clearer, more direct, and concise. It emphasizes the person or thing performing the action.
Passive voice is useful when:
The doer of the action is unknown or unimportant.
The action itself is more important than the doer (common in scientific or technical writing).
You want to avoid mentioning the doer of the action.
You want to emphasize the receiver of the action.
In the given sentence, using passive voice ("She was seen...") might be because the speaker wants to focus on 'She' and the fact that she was observed, rather than focusing strongly on 'We' who did the seeing.
Paper & answer key PDF ↗ Question 92archived
Select the most appropriate synonym of the given word.
PRECARIOUS
- A
dangerous
- B
valuable
- C
abundant
- D
premature
Show answer
A. dangerousUnderstanding PRECARIOUS and Its Synonym
The question asks us to select the most appropriate synonym for the word PRECARIOUS from the given options. A synonym is a word or phrase that means exactly or nearly the same as another word or phrase in the same language.
Let's first understand the meaning of the word PRECARIOUS.
PRECARIOUS means:
Not securely held or in position; dangerously likely to fall or collapse.
Dependent on chance circumstances; uncertain; insecure; risky.
So, the core meanings involve instability, insecurity, risk, and potential danger.
Analyzing Synonym Options for PRECARIOUS
Now let's look at the given options and see which one aligns best with the meaning of PRECARIOUS.
dangerous: This word means involving or posing a risk; likely to cause harm. This meaning aligns very closely with the idea of being insecure, risky, or likely to fall or collapse, which are key aspects of PRECARIOUS.
valuable: This word means having great worth, merit, or utility. This is related to worth or importance, not to stability, security, or risk. Thus, it is not a synonym for PRECARIOUS.
abundant: This word means existing or available in large quantities; plentiful. This refers to quantity, not to stability, security, or risk. Thus, it is not a synonym for PRECARIOUS.
premature: This word means happening or done before the usual or proper time; too early. This refers to timing, not to stability, security, or risk. Thus, it is not a synonym for PRECARIOUS.
Comparing the meanings, the word dangerous is the most appropriate synonym for PRECARIOUS as both words convey a sense of risk, insecurity, or potential harm.
Revision Table: Word Meanings
Word
Meaning
Related to PRECARIOUS?
PRECARIOUS
Unstable, insecure, risky, likely to fall or collapse; dependent on chance; uncertain.
(Original word)
dangerous
Involving or posing a risk; likely to cause harm.
Yes, aligns with risk and potential harm.
valuable
Having great worth.
No.
abundant
Existing in large quantities.
No.
premature
Happening too early.
No.
Additional Information on Synonyms
Understanding synonyms is crucial for expanding vocabulary and improving communication. Synonyms are words that have similar meanings. However, they are not always interchangeable in every context. The choice of synonym often depends on the specific nuance or register required.
For example, while 'dangerous' is a good general synonym for 'precarious', 'precarious' specifically emphasizes the instability or insecurity that leads to the danger. A cliff edge is inherently 'precarious' (unstable/risky position), and therefore 'dangerous'. A poisonous snake is 'dangerous', but you wouldn't typically describe the snake itself as 'precarious'. However, holding a poisonous snake would be a 'precarious' (risky/insecure) position.
Learning antonyms (words with opposite meanings) can also help reinforce vocabulary. Antonyms for PRECARIOUS could include safe, secure, stable, certain.
Paper & answer key PDF ↗ Question 93archived
Select the correctly spelt word.
- A
maintainence
- B
maintenence
- C
maintenance
- D
mentainance
Show answer
C. maintenanceIdentifying the Correct Spelling of Maintenance
The question asks us to select the correctly spelt word from the given options. We need to carefully examine each spelling to find the accurate one for the word 'maintenance'. The word 'maintenance' refers to the process of maintaining or preserving something, or the state of being maintained.
Analyzing the Spelling Options for Maintenance
Let's look at each option provided:
Option 1: maintainence
This spelling uses 'e' in the second syllable ('-tein-') and 'ence' at the end. The correct spelling does not use 'e' in the second syllable.
Option 2: maintenence
This spelling uses 'e' in the second syllable ('-ten-') and 'ence' at the end. This is a common misspelling, often confusing it with words like 'existence'.
Option 3: maintenance
This spelling uses 'a' in the second syllable ('-tain-') and 'ance' at the end. Let's consider if this is the correct form.
Option 4: mentainance
This spelling incorrectly starts with 'men-' instead of 'main-'.
The correct spelling of the word is 'maintenance'. It comes from the verb 'maintain'. While 'maintain' has 'ai' in the second syllable, the noun form 'maintenance' keeps the 'ai' sound but is spelled with 'ain' followed by 'tenance'. A common error is to spell it like 'maintenence', possibly due to the influence of similar-sounding words or confusion with the verb's ending.
Comparing Spellings of Maintenance
Let's summarize the spellings in a table:
Option
Spelling
Correctness
Reason
1
maintainence
Incorrect
Incorrect ending (-ence) and incorrect second syllable (maintain vs mainte)
2
maintenence
Incorrect
Incorrect second syllable (-ten-) and incorrect ending (-ence)
3
maintenance
Correct
Correct spelling with -ain- and -ance
4
mentainance
Incorrect
Incorrect beginning (ment vs main)
Based on standard English spelling rules and common usage, the correct spelling among the given options is 'maintenance'.
Revision Table: Common Spelling Errors
Many English words have tricky spellings. Reviewing common errors can help improve accuracy.
Word
Common Misspelling
Correct Spelling
Maintenance
Maintenence
Maintenance
Separate
Seperate
Separate
Receive
Recieve
Receive
Believe
Beleive
Believe
Occur
Occurrance
Occurrence
Additional Information on Spelling and Vocabulary
Understanding the origin of words (etymology) or related word forms can sometimes help with spelling. The word 'maintenance' is a noun derived from the verb 'maintain'. Both words share the core meaning related to keeping something in good condition or continuing something. Paying attention to specific letter patterns, like '-ance' vs. '-ence' endings in nouns, is crucial for correct spelling in English vocabulary.
Paper & answer key PDF ↗ Question 94archived
Select the most appropriate synonym of the given word.
STERILE
- A
barren
- B
productive
- C
Fecund
- D
sordid
Show answer
A. barrenUnderstanding the Question: Finding the Synonym for Sterile
The question asks us to identify the word from the given options that is the most appropriate synonym for the word "STERILE". A synonym is a word or phrase that means exactly or nearly the same as another word or phrase in the same language.
Defining the Word "STERILE"
The word STERILE primarily has a few meanings:
(Of a person, animal, or plant) unable to produce offspring, fruit, or seeds; infertile.
(Of land) too poor to produce much or any vegetation.
Free from bacteria or other living microorganisms; totally clean.
Lacking in interest, vitality, or imagination.
In the context of finding a synonym among the given options, the first two meanings relating to the inability to produce or grow are the most relevant.
Analyzing the Options
Let's examine each option provided:
barren: (Of land) too poor to produce much or any vegetation; (of a female animal) not able to produce offspring. This meaning is very close to the primary meanings of sterile related to inability to produce life or growth.
productive: Producing or able to produce large amounts of goods, crops, or other commodities; achieving or producing a significant amount or result. This is essentially the opposite of sterile or barren.
Fecund: Producing or capable of producing an abundance of offspring or new growth; profusely or highly inventive. This is also an antonym (opposite) of sterile.
sordid: Involving ignoble actions and motives; arousing moral distaste and contempt; dirty or squalid. This meaning is unrelated to sterile in any common context.
Identifying the Most Appropriate Synonym
Based on the analysis of the meanings, the word barren is the most appropriate synonym for sterile, especially when referring to the inability to produce vegetation or offspring.
Understanding Synonyms in Vocabulary
Synonyms are important for expanding vocabulary and expressing ideas with variety and precision. When choosing the best synonym, it's crucial to consider the specific context in which the word is used, although here we are looking for the general best match.
Word
Meaning Relevant to Question
Relationship to STERILE
STERILE
Unable to produce life or growth; infertile; barren.
Target word
barren
Unable to produce vegetation or offspring.
Synonym
productive
Able to produce abundantly.
Antonym
Fecund
Capable of producing abundantly.
Antonym
sordid
Dirty, squalid, morally distasteful.
Unrelated
Conclusion
Comparing the options, 'barren' is the only word that shares a core meaning with 'sterile' regarding the inability to produce life or growth. Therefore, 'barren' is the most appropriate synonym.
Revision Table: Key Vocabulary
Word
Meaning
Example Usage
Sterile
Unable to produce; free from germs
The sterile land could not grow crops. / The surgical instruments were sterile.
Barren
Unable to produce; empty
A barren desert landscape. / A barren discussion with no new ideas.
Productive
Producing a lot; fruitful
A productive farmland. / A productive meeting.
Fecund
Producing abundant growth or offspring; fertile
A fecund imagination. / A fecund plot of land.
Sordid
Dirty, squalid; morally unpleasant
A sordid tale of crime and betrayal. / Sordid living conditions.
Additional Information: Antonyms and Related Terms
Understanding antonyms (words with opposite meanings) can also help clarify a word's meaning. The antonyms for sterile (in the sense of productive) include fertile, productive, and fecund.
Related terms for sterile (in the sense of free from germs) include aseptic, sanitized, and disinfected. However, this meaning was not the one relevant to the given options.
By studying synonyms and antonyms together, you can build a stronger vocabulary and better understand the nuances of word meanings.
Paper & answer key PDF ↗ Question 95archived
The question below consists of a set of labelled sentences. Out of the four options given, select the most logical order of the sentences to form a coherent paragraph.
A. The students often go about their business, singing along in the corridors.
B. But for the students of St. Ambrose High School, it no longer dictates their day.
C. A bell can sound gloomy or cheerful depending on when it is rung.
D. It has been scrapped in favor of music which now breaks up the timetable of the school
- A
BDAC
- B
CBDA
- C
ACBD
- D
CADB
Show answer
B. CBDAUnderstanding Sentence Reordering for Paragraph Coherence
The question asks us to arrange a set of labelled sentences (A, B, C, and D) into a logical sequence to form a coherent paragraph. This requires identifying the topic, the main idea, supporting details, and the conclusion or effect.
Analyzing Each Sentence
Let's look at each sentence individually to understand its potential role:
Sentence A: "The students often go about their business, singing along in the corridors." This sentence describes an action of the students – singing. It sounds like an effect or result of something mentioned earlier.
Sentence B: "But for the students of St. Ambrose High School, it no longer dictates their day." This sentence introduces a specific group (students of St. Ambrose High School) and contrasts their situation ("But...") regarding "it" (likely referring to a bell) with a general idea. It suggests a change or exception.
Sentence C: "A bell can sound gloomy or cheerful depending on when it is rung." This sentence is a general statement about bells and how their sound can be perceived. It seems like a good potential opening sentence as it introduces the main subject: a bell.
Sentence D: "It has been scrapped in favor of music which now breaks up the timetable of the school." This sentence explains what replaced "it" (the bell) at a specific place (likely St. Ambrose High School, linking it to sentence B). It provides the reason why "it" no longer dictates the day.
Finding the Logical Flow to Create a Coherent Paragraph
We need to find an order where sentences flow smoothly from one to the next, building a clear idea. Let's try connecting the sentences based on our analysis:
Starting with C: Sentence C makes a general statement about bells. This is a good way to introduce the topic before talking about a specific situation.
Following C with B: Sentence B contrasts the general idea of a bell with the situation at St. Ambrose High School ("But..."). It says the bell "no longer dictates their day." This logically follows the introduction of bells in C and narrows the focus to a specific case.
Following B with D: Sentence D explains *why* the bell doesn't dictate the day at St. Ambrose High School mentioned in B. It says the bell "has been scrapped in favor of music." This provides the reason for the situation described in B.
Following D with A: Sentence A describes the consequence or effect of music replacing the bell (as stated in D). The students "sing along in the corridors." This action is a direct result of music being present instead of a bell.
The order C → B → D → A creates a smooth, logical flow:
General statement about bells (C).
Exception/contrast at St. Ambrose School regarding bells (B).
Explanation for the exception - music replaced bells (D).
Result/effect of the replacement on students (A).
Thus, the logical order of the sentences to form a coherent paragraph is CBDA.
Constructing the Coherent Paragraph
Let's put the sentences together in the CBDA order:
C. A bell can sound gloomy or cheerful depending on when it is rung.
B. But for the students of St. Ambrose High School, it no longer dictates their day.
D. It has been scrapped in favor of music which now breaks up the timetable of the school.
A. The students often go about their business, singing along in the corridors.
Reading this paragraph aloud confirms that it flows logically and makes sense, forming a coherent narrative about how St. Ambrose High School replaced their school bell with music and the positive effect it has on students.
Sentence Analysis and Linkages
Sentence
Content
Role
Logical Link
C
General statement about bell mood.
Introduction of topic (bell)
Starts the paragraph.
B
Contrast for St. Ambrose school, bell doesn't dictate day.
Specific case/Contrast
Follows C, introduces specific school and change regarding bell.
D
Bell replaced by music.
Explanation/Reason
Follows B, explains *why* the bell doesn't dictate the day at St. Ambrose.
A
Students sing along.
Effect/Result
Follows D, describes the consequence of music replacing the bell.
Revision Table - Sentence Arrangement
Reviewing the process of arranging sentences involves checking for chronological order (if applicable), cause-and-effect relationships, general-to-specific flow, and consistent pronoun reference.
Check if introductory sentences come first.
Look for connecting words like "but," "therefore," "however," which indicate relationships between ideas.
Ensure pronouns (like "it" in B and D) refer clearly to a noun mentioned earlier (like "A bell" in C).
Verify that the paragraph has a single main topic.
Additional Information - Paragraph Coherence
Paragraph coherence is achieved when all sentences are logically connected and flow smoothly, making the paragraph easy to understand. Key elements contributing to coherence include:
Logical Order: Arranging sentences in an order that makes sense (e.g., chronological, spatial, order of importance, general to specific).
Transitions: Using words or phrases (like "but," "instead," "as a result") to show relationships between ideas.
Repetition of Key Terms: Repeating important nouns or using synonyms to maintain focus.
Pronoun Reference: Using pronouns (he, she, it, they, this, that, these, those) that clearly refer back to previously mentioned nouns.
In this question, the logical order from general (C) to specific (B), followed by an explanation (D) and its effect (A), creates a highly coherent paragraph.
Paper & answer key PDF ↗ Question 96archived
Select the most appropriate option to fill in blank No.5.
- A
venturing
- B
pioneering
- C
risking
- D
climbing
Show answer
A. venturingSolving the Fill-in-the-Blanks Passage
The passage discusses the importance of maintaining balance and avoiding extremes, drawing wisdom from ancient Indian sages. It warns against "taking anything too far" or being "too radical," highlighting the negative consequences, specifically environmental degradation, as an example of what happens when limits are exceeded.
We need to choose the most appropriate word for blank No. 5. The sentence reads: "The unfortunate results of (5)______- too far are obvious in the environmental degradation." The blank requires a word that, when combined with "too far," describes the action that leads to unfortunate results like environmental degradation.
Analyzing Options for Blank 5
Let's examine each option provided for blank No. 5:
venturing: To venture means to take a risk or embark on a new or risky course of action. "Venturing too far" implies going beyond sensible or safe limits, taking excessive risks, or pushing boundaries too much. This fits the context of the passage, which warns against extremes that lead to negative outcomes like environmental damage.
pioneering: To pioneer means to be among the first to explore or settle a new area or develop a new idea or activity. "Pioneering too far" is not a standard phrase and doesn't logically connect to the idea of negative consequences from exceeding limits in a general sense discussed here.
risking: To risk means to expose something valued to danger. While environmental degradation is a result of risks taken, the phrase "risking too far" is grammatically awkward and less idiomatic than "venturing too far." We might say "taking risks" or "risking too much," but not typically "risking too far" in this context.
climbing: To climb means to ascend something. "Climbing too far" refers specifically to a physical action of scaling a height. This doesn't fit the metaphorical or general sense of exceeding limits discussed in the passage related to societal actions leading to environmental degradation.
Selecting the Most Appropriate Word for Blank 5
Based on the analysis, the word that best fits the context of exceeding limits and resulting in negative consequences like environmental degradation is "venturing." The phrase "venturing too far" effectively captures the idea of pushing beyond what is safe, balanced, or sustainable.
Therefore, the completed part of the sentence for blank 5 should be "venturing too far".
Completed Sentence Segment for Blank 5
The unfortunate results of venturing too far are obvious in the environmental degradation.
Blank No.
Most Appropriate Option
Reasoning
5
venturing
Fits the context of exceeding sensible limits or boundaries, leading to negative consequences like environmental degradation.
Revision Table: Blank 5 Analysis
Option
Suitability for Blank 5
Explanation
venturing
Most Appropriate
"Venturing too far" means going beyond safe limits, which leads to negative outcomes like environmental harm.
pioneering
Not Suitable
Grammatically and contextually inappropriate.
risking
Not Suitable
"Risking too far" is not idiomatic English; "taking risks" or "risking too much" would be used.
climbing
Not Suitable
Refers only to physical ascent; doesn't fit the general context of the passage.
Additional Information: Understanding Cloze Tests
Cloze tests are exercises where words are removed from a passage, and you have to fill in the blanks. They test your understanding of context, vocabulary, grammar, and idiom. To solve cloze tests effectively:
Read the entire passage first to understand the overall meaning and tone.
Read the sentence containing the blank carefully.
Look at the words around the blank (collocations, prepositions, grammatical structure).
Consider each option provided.
Think about the meaning of each option and whether it makes sense grammatically and contextually in the sentence and the overall passage.
Sometimes, trying out each option in the sentence helps you hear which one sounds correct.
In this specific blank, understanding the consequence (environmental degradation) helps determine what kind of action ("venturing too far") leads to it.
Paper & answer key PDF ↗ Question 97archived
In the sentence identify the segment which contains the grammatical error.
In the northern suburbs of Bengaluru, home to the bulk of the information technology industry, the water crisis is even worst.
- A
is even worst
- B
the water crisis
- C
In the northern suburbs
- D
home to the bulk of
Show answer
A. is even worstIdentifying Grammatical Errors in Sentences
The question asks us to identify the segment in the given sentence that contains a grammatical error. Let's examine the sentence provided:
"In the northern suburbs of Bengaluru, home to the bulk of the information technology industry, the water crisis is even worst."
Analyzing the Sentence Structure and Segments
The sentence can be broken down into several parts:
"In the northern suburbs of Bengaluru," - This is a prepositional phrase indicating location.
"home to the bulk of the information technology industry," - This is an appositive phrase describing the northern suburbs.
"the water crisis" - This is the subject of the main clause.
"is even worst" - This is the predicate, containing the verb and an adjective phrase describing the subject's state.
Focusing on the Potential Error
The potential error lies in the phrase "is even worst". Let's analyze the word "worst".
Worst is the superlative form of the adjective "bad" and the adverb "badly".
The degrees of comparison for "bad" are: bad (positive), worse (comparative), worst (superlative).
The word "even" is an adverb often used to emphasize a comparison.
When we use "even" with an adjective to intensify the degree, it is typically followed by the comparative form of the adjective (e.g., even better, even faster, even colder, even worse).
The phrase "even worst" uses the superlative form "worst" after "even". This construction is generally grammatically incorrect when comparing degrees of a quality or intensifying a negative condition. We would use the comparative form "worse" in this context to indicate a greater degree of badness.
For example:
Correct: "The weather is bad, but tomorrow it will be even worse." (Comparing degrees of bad weather)
Correct: "That was a bad decision, but this new one is even worse." (Comparing degrees of bad decisions)
In the given sentence, "the water crisis is even worst", the intention is to say that the water crisis in the northern suburbs is bad, and its condition is intensified or is of a higher degree of badness compared to perhaps other areas or a general state. Therefore, the comparative form "worse" should be used instead of the superlative form "worst".
The correct phrasing should be "the water crisis is even worse".
Identifying the Incorrect Segment
Based on the analysis, the segment containing the grammatical error is "is even worst".
Revision Table: Degrees of Comparison for 'Bad'
Positive Degree
Comparative Degree
Superlative Degree
bad
worse
worst
Additional Information: Using 'Even' with Adjectives
The adverb 'even' is frequently used for emphasis, especially when making comparisons or highlighting something unexpected or extreme.
When used with comparative adjectives or adverbs, 'even' strengthens the comparison: "She is fast, but he is even faster."
When used with superlative adjectives or adverbs, 'even' often highlights the extreme nature within a group: "This is the worst movie I've seen, but even the worst movies have some redeeming quality." (Here, 'even the worst' means 'including the worst'). This usage is different from intensifying the degree of the quality itself.
In the sentence "the water crisis is even worst", 'even' is used to intensify the degree of the water crisis's severity, requiring the comparative form 'worse'.
Paper & answer key PDF ↗ Question 98archived
Select the correctly spelt word.
- A
Adolescense
- B
Adolesense
- C
Adolescence
- D
Adolescance
Show answer
C. AdolescenceCorrect Spelling of Adolescence
This question asks us to identify the correctly spelled word among the given choices. The word in question relates to the developmental stage between childhood and adulthood. It's crucial to pay attention to the specific letters and their order, especially common suffixes like '-ence' versus '-ance' or '-ense'.
Analyzing Spelling Options for Adolescence
Let's look closely at each option to determine the correct spelling:
Adolescense: This spelling is incorrect. It incorrectly uses the suffix '-ense'. The standard English spelling requires '-ence'.
Adolesense: This spelling is incorrect. It is missing the letter 'c' that should appear before the 'e' in the suffix.
Adolescence: This is the correct spelling. It accurately reflects the standard English spelling convention for this word, using the '-cence' ending.
Adolescance: This spelling is incorrect. It mistakenly uses the suffix '-ance', which is not appropriate for this particular word.
Understanding the Word 'Adolescence'
Adolescence is defined as the process of maturing or the period of development between childhood and adulthood. It's a common word, and knowing its correct spelling is important for effective writing.
The correct spelling relies on the '-cence' suffix. Many English words describing states or qualities use this ending (e.g., 'difference', 'luminescence'). Remembering this pattern helps in identifying the correctly spelled word.
Therefore, the option Adolescence is the one that is correctly spelled.
Paper & answer key PDF ↗ Question 99archived
Select the most appropriate option to fill in blank No.3.
- A
caretaker
- B
careless
- C
careful
- D
carefree
Show answer
C. carefulSolving Cloze Test: Finding the Right Word for Blank 3
The passage discusses the importance of balance, drawing wisdom from Indian sages. It warns against taking actions or ideas to an extreme, or being too radical, highlighting environmental degradation as a consequence of such imbalance.
The sentence in question is: "This means we should be (3)______ not to take anything too far (4)______ be too radical."
We need to select the most appropriate word for blank (3) that fits the context of avoiding extremes and maintaining balance.
Analyzing Options for Blank 3
Let's look at the given options for blank (3):
caretaker: A caretaker is someone who looks after a building or property, or someone who cares for a person. This word doesn't fit the context of how one should approach actions or ideas to maintain balance.
careless: Careless means not paying enough attention, resulting in mistakes or damage. Being careless would likely lead one to take things too far or be too radical, which is the opposite of what the passage advocates.
careful: Careful means giving a lot of attention to avoid danger or mistakes; cautious. Being careful implies taking measured steps and considering the consequences, which aligns perfectly with the idea of avoiding extremes and maintaining balance.
carefree: Carefree means free from anxiety or responsibility. While positive in some contexts, being carefree doesn't suggest the necessary caution required to avoid going too far or being too radical.
Determining the Most Appropriate Word
The sentence structure "be (3)______ not to take anything too far" suggests that the word in blank (3) should describe a state or quality that prevents one from going to extremes. The word "careful" precisely means exercising caution and attention to avoid undesirable outcomes, such as taking things too far or being too radical. Therefore, "careful" is the most fitting word for blank (3) in this context.
Substituting "careful" into the sentence:
"This means we should be careful not to take anything too far..."
This completes the meaning logically, emphasizing the need for caution to maintain balance.
Option
Meaning
Fit in Context
Caretaker
Person who looks after something/someone
Poor fit
Careless
Not paying attention; negligent
Opposite meaning required
Careful
Paying attention to avoid danger/mistakes; cautious
Excellent fit
Carefree
Free from anxiety/responsibility
Poor fit
Conclusion
Based on the analysis of the meaning of each option and the context of the passage, the most appropriate word to fill blank No. 3 is "careful".
Revision Table: Key Vocabulary for Cloze Tests
Word
Definition
Example Usage
Careful
Avoiding danger or mistakes; cautious.
Be careful when crossing the road.
Careless
Not giving enough attention or thought to avoid harm or mistakes.
A careless mistake in the calculation.
Caretaker
A person employed to look after a building.
The school's caretaker locks up at night.
Carefree
Free from anxiety or responsibility.
Children often have a carefree attitude.
Balance
An even distribution of weight enabling someone or something to remain upright. Also, a situation in which different elements are equal or in the correct proportions.
Maintain a healthy work-life balance.
Radical
Relating to or affecting the fundamental nature of something; far-reaching or thorough. (Often implying extreme change).
They proposed a radical solution to the problem.
Additional Information: Approaching Cloze Test Questions
Solving cloze test questions effectively requires a combination of vocabulary knowledge, understanding of grammar, and the ability to comprehend the context of the passage. Here are some tips:
Read the entire passage first: Get a general understanding of the topic, tone, and flow of ideas.
Focus on the sentence with the blank: Read the sentence carefully, paying attention to the words before and after the blank.
Look for grammatical clues: Is the missing word a noun, verb, adjective, adverb, or preposition? What tense or form is needed?
Consider the context: How does the sentence relate to the surrounding sentences and the overall theme of the passage?
Try each option: Mentally (or physically) insert each given option into the blank and see which one makes the most sense logically and grammatically in the context.
Eliminate incorrect options: Rule out options that are grammatically incorrect or don't fit the meaning of the passage.
Check for consistency: Ensure your chosen word makes the completed sentence flow smoothly and contributes logically to the passage's meaning.
Cloze tests assess your ability to understand how words function together to create coherent meaning in a text. Practicing with different types of passages and question styles can significantly improve your performance.
Paper & answer key PDF ↗ Question 100archived
Select the correct passive form of the given sentence.
The enemy will have seized the fort before nightfall.
- A
The fort will have been seized by the enemy before nightfall.
- B
The fort would have been seized by the enemy before nightfall.
- C
The enemy will seize the fort before nightfall
- D
The enemy will be seized by the fort before nightfall
Show answer
A. The fort will have been seized by the enemy before nightfall.Understanding Active and Passive Voice Transformation
This question asks us to convert a sentence from active voice to passive voice. The original sentence is "The enemy will have seized the fort before nightfall."
First, let's identify the key components of the active sentence:
Subject: The enemy (performs the action)
Verb: will have seized (the action)
Object: the fort (receives the action)
Time Phrase: before nightfall
The verb tense used is the future perfect tense (will have + past participle). The structure for the future perfect tense in active voice is Subject + will have + V3 (past participle) + Object.
Converting Future Perfect Active to Passive Voice
To change a future perfect sentence from active voice to passive voice, we follow these steps:
Make the object of the active sentence the subject of the passive sentence.
Use the appropriate form of the auxiliary verb "will have been".
Use the past participle (V3) of the main verb.
Add "by" followed by the original subject (the agent), if necessary (often included when the agent is important).
Keep other parts of the sentence (like time phrases) in their place.
Applying these steps to the sentence "The enemy will have seized the fort before nightfall":
Original object "the fort" becomes the new subject: The fort
Auxiliary verb for future perfect passive: will have been
Past participle of "seized" is: seized
Original subject "The enemy" becomes the agent: by the enemy
Time phrase: before nightfall
Combining these parts, the passive voice sentence is: The fort will have been seized by the enemy before nightfall.
Analyzing the Given Options for Passive Form
Let's examine each option provided to find the correct passive transformation:
The fort will have been seized by the enemy before nightfall.
This sentence uses "The fort" as the subject, "will have been seized" as the future perfect passive verb, and includes the agent "by the enemy". It correctly follows the rules for converting future perfect active to passive voice. This option matches our derived sentence.
The fort would have been seized by the enemy before nightfall.
This option uses "would have been seized". While grammatically correct as a construction (conditional perfect passive), it changes the modality/tense from "will have been seized" (future perfect passive) of the original sentence. The original sentence uses 'will', indicating a future certainty (or strong prediction). Replacing 'will' with 'would' changes the meaning to a hypothetical or conditional situation. Therefore, this is not the correct passive form of the given active sentence.
The enemy will seize the fort before nightfall
This sentence is still in the active voice. The subject "The enemy" is performing the action "will seize". The tense is future simple (will + base verb), not future perfect. This is not the correct passive form.
The enemy will be seized by the fort before nightfall
This sentence incorrectly makes "The enemy" the subject and "the fort" the agent ("by the fort"). It suggests the fort is seizing the enemy, which is the opposite meaning of the original sentence. Also, the verb tense is future simple passive ("will be seized"), not future perfect passive. This is incorrect.
Based on the analysis, only option 1 is the correct passive voice transformation of the given future perfect active sentence.
Revision Table: Active vs. Passive Voice
Aspect
Active Voice
Passive Voice
Focus
Subject performing the action
Action and/or the object receiving the action
Structure (General)
Subject + Verb + Object
Object + be + V3 + by + Subject (optional)
Subject's Role
Doer of the action
Receiver of the action
Use Case
When the doer is important or clear
When the action or receiver is important, or the doer is unknown/unimportant
Additional Information: Passive Voice and Tenses
Converting active voice to passive voice depends heavily on the tense of the original verb. Here are some common tense transformations:
Simple Present: Active: Subject + V1(s/es) + Object. Passive: Object + is/am/are + V3 + by Subject.
Simple Past: Active: Subject + V2 + Object. Passive: Object + was/were + V3 + by Subject.
Simple Future: Active: Subject + will + V1 + Object. Passive: Object + will be + V3 + by Subject.
Present Continuous: Active: Subject + is/am/are + V1+ing + Object. Passive: Object + is/am/are + being + V3 + by Subject.
Past Continuous: Active: Subject + was/were + V1+ing + Object. Passive: Object + was/were + being + V3 + by Subject.
Present Perfect: Active: Subject + has/have + V3 + Object. Passive: Object + has/have + been + V3 + by Subject.
Past Perfect: Active: Subject + had + V3 + Object. Passive: Object + had + been + V3 + by Subject.
Future Perfect: Active: Subject + will have + V3 + Object. Passive: Object + will have + been + V3 + by Subject. (This was the tense in our question)
Understanding these patterns helps in correctly transforming sentences between active and passive voices across different tenses.
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