Prelims Solution

Q. With respect to what are called denomination of religion, if everyone is left to be a judge of his own religion, there is no such things as religion that is wrong; but if they are to be a judge of each other’s religion, there is no such thing as a religion that is right, and therefore all the world is right or all the world is wrong in the matter of religion.

Q. With respect to what are called denomination of religion, if everyone is left to be a judge of his own religion, there is no such things as religion that is wrong; but if they are to be a judge of each other’s religion, there is no such thing as a religion that is right, and therefore all the world is right or all the world is wrong in the matter of religion.

Q.1 What is the most logical assumption that can be made from the passage given above?
(a) No man can live without adhering to some religious denomination.
(b) It is the duty of everyone to propagate one’s religious denomination.
(c) Religious denominations tend to ignore the unity of man.
(d) Men do not understand their own religious denomination.

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

Religious denominations

Q1: Correct Answer – (c) Religious denominations tend to ignore the unity of man.
Explanation – The most logical assumption from the passage is © Religious denominations tend to ignore the unity of man.

This option suggests that different religious denominations may focus on their own beliefs and practices rather than recognizing the commonalities among all people. In other words, religious denominations may overlook the fact that all humans share a common bond and instead focus on their differences.

Q. With respect to what are called denomination of religion, if everyone is left to be a judge of his own religion, there is no such things as religion that is wrong; but if they are to be a judge of each other’s religion, there is no such thing as a religion that is right, and therefore all the world is right or all the world is wrong in the matter of religion. Read More »

Q. Which day is 10th October, 2027 ?

Q. Which day is 10th October, 2027 ?

(a) Sunday
(b) Monday
(c) Tuesday
(d) Saturday
Correct Answer: (a) Sunday

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

10th October 2027 Day ?

We know that, 10th October 2021 is a Sunday. (The day of UPSC CSE, 2021 Preliminary exam)

So, 10th October 2022 will be Sunday + 1, i.e. Monday.
10th October 2023 will be Monday + 1, i.e. Tuesday.
10th October 2024 will be Tuesday + 2, i.e. Thursday. We added 2, as 2024 is a leap year.
10th October 2025 will be Thursday + 1, i.e. Friday.
10th October 2026 will be Friday + 1, i.e. Saturday.
10th October 2027 will be Saturday + 1, i.e. Sunday.

Q. Which day is 10th October, 2027 ? Read More »

Question: What day is the fourteenth of the given month?

Q. Consider two Statements and a Question:

Statement 1: The last day of the month is a Wednesday.
Statement 2: The third Saturday of the month was the seventeenth day.

Question: What day is the fourteenth of the given month?

Which one of the following is correct in respect of the Statements and the Question?
(a) Statement 1 alone is sufficient to the answer of the Question
(b) Statement 2 alone is sufficient to answer the Question
(c) Both Statement 1 and Statement 2 are required to answer the Question
(d) Neither Statement 1 alone nor Statement 2 alone is sufficient to answer the Question
Correct Answer: (b) Statement 2 alone is sufficient to answer the Question

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

Given Information:

1. Statement 1: Month ends on Wednesday

2. Statement 2: Third Saturday is on 17th

Using Statement 1 alone:
– Only knows last day is Wednesday
– Month could be 30 or 31 days
– First day could vary
– Cannot determine 14th day
– Not sufficient

Using Statement 2 alone:
– Third Saturday = 17th
– Second Saturday = 10th
– First Saturday = 3rd
– Working backwards:
1st day must be Thursday
14th must be Wednesday
– Sufficient to answer

Using Both Statements:
– Statement 2 alone gives the answer
– Statement 1 not needed

Answer: (b) Statement 2 alone is sufficient

The 14th of the month is Wednesday, determined solely from Statement 2.

Question: What day is the fourteenth of the given month? Read More »

Q. Half of the villagers of a certain village have their own houses. One-fifth of the villagers cultivate paddy. One-third of the villagers are literate. Four-fifth of the villagers are under 25 years of age. Which one of the following statements is certainly correct?

Q. Half of the villagers of a certain village have their own houses. One-fifth of the villagers cultivate paddy. One-third of the villagers are literate. Four-fifth of the villagers are under 25 years of age. Which one of the following statements is certainly correct?

(a) All the villagers who have their own houses are literate.
(b) Some villagers are under 25 years of age are literate.
(c) Only half of the villagers who cultivate paddy are literate.
(d) No villager under 25 years of age has his own house.
Correct Answer: (b) Some villagers are under 25 years of age are literate.

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

Half of the villagers of a certain village

The correct answer is (b) Some villagers under 25 years of age are literate. This is because the given information states that one-third of the villagers are literate and four-fifth of the villagers are under 25 years of age.

Therefore, it is possible that some villagers who are under 25 years of age are also literate because one third is larger than one-fifth.

half of the villagers

Q. Half of the villagers of a certain village have their own houses. One-fifth of the villagers cultivate paddy. One-third of the villagers are literate. Four-fifth of the villagers are under 25 years of age. Which one of the following statements is certainly correct? Read More »

Q. At which one of the following times, do the hour hand the minute hand of the clock make an angle of 180° with each other?

Q. At which one of the following times, do the hour hand the minute hand of the clock make an angle of 180° with each other?

(a) At 7:00 hours
(b) Between 7:00 hours and 7:05 hours
(c) At 7:05 hours
(d) Between 7:05 hours and 7:10 hours
Correct Answer: (d) Between 7:05 hours and 7:10 hours

Question from UPSC Prelims 2021 CSAT Paper

Explanation :

Hour hand and Minute hand of the clock

Let’s solve this step by step:

1) When hands make 180°, they point in opposite directions.

2) At 7:00:
– Hour hand moves (7/12 × 360°) = 210° from start
– Minute hand at 0°
– Angle = 210° (not 180°)

3) In 1 hour:
– Hour hand moves 30°
– Minute hand moves 360°

4) In 1 minute:
– Hour hand moves 0.5°
– Minute hand moves 6°

5) At 7:05:
– Hour hand: 210° + (5 × 0.5°) = 212.5°
– Minute hand: 5 × 6° = 30°
– Angle = 182.5° (not 180°)

6) Between 7:05 and 7:10, at approximately 7:06, the hands form exactly 180°.

Therefore, the answer is (d) Between 7:05 hours and 7:10 hours.

Q. At which one of the following times, do the hour hand the minute hand of the clock make an angle of 180° with each other? Read More »

Q. In a code language ‘MATHEMATICS’ is written as ‘LBSIDNZUHDR’. How is CHEMISTRY’ written in that code language?

Q. In a code language ‘MATHEMATICS’ is written as ‘LBSIDNZUHDR’. How is CHEMISTRY’ written in that code language?

(a) DIDLHRSSX
(b) BIDNHTSSX
(c) BIDLHTSSX
(d) DGFLIRUQZ
Correct Answer: (b) BIDNHTSSX

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

MATHEMATICS – CHEMISTRY

According to the pattern:
For odd positions (1,3,5,7,9,11): Subtract 1
For even positions (2,4,6,8,10): Add 1

MATHEMATICS → LBSIDNZUHDR
CHEMISTRY → BIDLHTSSX

Therefore, answer is (c) BIDLHTSSX

Q. In a code language ‘MATHEMATICS’ is written as ‘LBSIDNZUHDR’. How is CHEMISTRY’ written in that code language? Read More »

Q. P scored 40 marks more than Q in an examination. If Q scored 10% less marks than P, then how much did Q score.

Q. P scored 40 marks more than Q in an examination. If Q scored 10% less marks than P, then how much did Q score.

(a) 360
(b) 380
(c) 400
(d) 420
Correct Answer: (a) 360

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

P scored 40 marks more than Q in an examination

Given:
– P scored x marks
– P scored 40 marks more than Q
– Q scored 10% less than P

Step 1: Initial Equations
– Q’s marks = x – 40 (40 less than P)
– Q’s marks = 0.9x (10% less than P)

Step 2: Solve for x
– x – 40 = 0.9x
– x – 0.9x = 40
– 0.1x = 40
– x = 400

Final Scores:
– P scored 400 marks
– Q scored 360 marks (400 – 40)

Q. P scored 40 marks more than Q in an examination. If Q scored 10% less marks than P, then how much did Q score. Read More »

Q. In the series_b_a_ba_b_abab_aab; fill in the six blanks (_) using one of the following given four choices such that the series follows a specific order.

Q. In the series_b_a_ba_b_abab_aab; fill in the six blanks (_) using one of the following given four choices such that the series follows a specific order.

(a) bababa
(b) baabba
(c) bbaabb
(d) ababab
Correct Answer: (d) ababab

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

The given series is: _b_a_ba_b_abab_aab

The pattern being followed in the above series is: abb, then aab. Again abb, and then aab, and so on.
The blanks have been highlighted below:
a b b / a a b / a b b / a ab / ab b / aab

Q. In the series_b_a_ba_b_abab_aab; fill in the six blanks (_) using one of the following given four choices such that the series follows a specific order. Read More »

Q. There are three points P,Q and R on a straight line such that PQ:QR-3:5. If n is the number of possible values of PQ:PR, then what is n equal to ?

Q. There are three points P,Q and R on a straight line such that PQ:QR-3:5. If n is the number of possible values of PQ:PR, then what is n equal to ?

(a) 1
(b) 2
(c) 3
(d) 4
Correct Answer: (b) 2

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

Three points P,Q and R on straight line

CASE – 1
Assuming PQ = 3x, QR = 5x and PR = PQ + QR, we get
PQ : PR = 3x : (3x + 5x)
⇒ PQ : PR = 3 : 8

Three points P, Q, R on a line

CASE – 2
Assuming PQ = 3x, QR = 5x and PR = QR – PQ, we get
PQ : PR = 3x : (5x – 3x)
⇒ PQ : PR = 3 : 2

So, we have n = 2 possible values.

Q. There are three points P,Q and R on a straight line such that PQ:QR-3:5. If n is the number of possible values of PQ:PR, then what is n equal to ? Read More »

Q. X said to Y, “”At the time of your birth I was twice as old as you are at present.”” If the present age of X is 42 years, then consider the following statements:

Q. X said to Y, “At the time of your birth I was twice as old as you are at present.” If the present age of X is 42 years, then consider the following statements:

1. 8 years ago, the age of X was five times the age of Y.
2. After 14 years, the age of X would be two times the age of Y.

Which of the above statements is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Correct Answer: (b) 2 only

Question from UPSC Prelims 2021 CSAT Paper

Explanation : 

X & Y Age Relationship Analysis

Given:
– X’s present age = 42 years
– At Y’s birth, X was twice Y’s current age
– Let Y’s present age = y

Step 1: Initial Equation
– 42 – y = 2y (X’s age at Y’s birth = 2 × Y’s current age)
– 42 = 3y
– Therefore, y = 14 (Y’s current age)

Step 2: Testing Statement 1 (8 years ago)
– X’s age: 42 – 8 = 34
– Y’s age: 14 – 8 = 6
– Check: 34 ≠ 5 × 6 (30)
– Result: Statement 1 is false

Step 3: Testing Statement 2 (14 years later)
– X’s age: 42 + 14 = 56
– Y’s age: 14 + 14 = 28
– Check: 56 = 2 × 28
– Result: Statement 2 is true

Answer: Only Statement 2 is correct.

Q. X said to Y, “”At the time of your birth I was twice as old as you are at present.”” If the present age of X is 42 years, then consider the following statements: Read More »