CSAT (Paper II): previous-year questions
1280 real UPSC Prelims questions (2011–2026) with the official answer and a clear explanation. 400 of them came in the last five papers.
How often UPSC asks this
Questions per year, counted from the official papers.
Subtopics
Arrangements, ranking, ordering and puzzles
142 questions
Clocks and calendars
5 questions
Coding-decoding, series, patterns, cubes, dice and visual reasoning
110 questions
Communication, interpersonal skills and decision-making
10 questions
Counting, permutations, combinations and probability
1 questions
Directions, blood relations and Venn diagrams
60 questions
General English: grammar, vocabulary and comprehension
20 questions
General Hindi: grammar, vocabulary, dialects and comprehension
25 questions
Geometry and mensuration
26 questions
Number system and basic algebra (divisibility, HCF/LCM, remainders, digits, equations)
196 questions
Percentages, profit and loss, discount, simple and compound interest
47 questions
Ratio, proportion, averages, mixtures and alligation
47 questions
Syllogisms, statements and conclusions, assumptions and arguments
89 questions
Time and work; pipes and cisterns
2 questions
Time, speed and distance; trains, boats and streams; races
48 questions
Attempt the questions
Newest papers first. Tap an option; the answer and the reason appear instantly.
Six students A, B, C, D, E and F appeared in several tests. Either C or F scores the highest. Whenever C scores the highest, then E scores the least. Whenever F scores the highest, B scores the least. In all the tests they got different marks; D scores higher than A, but they are close competitors; A scores higher than B; C scores higher than A.
If B scores the least, the rank of C will be
Answer (d) & explanation
C can be second or third (d). Step 1: if C were first, E would be last. But B is last, so C is not first. So F is first. Step 2: "close competitors" puts D just above A. C must be above A, and A above B. Step 3: two orders work: F, C, E, D, A, B and F, E, C, D, A, B. In the first, C is 2nd; in the second, C is 3rd. So C is second or third. Options (a), (b) and (c) give only one possibility.
Tip: when clues leave two valid orders, the answer must cover both. "Second or third" type options exist for exactly this case.
Answer as per the official UPSC answer key.
Read the passage
The rural poor across the world, including India, have contributed little to human-induced climate change, yet they are on the frontline in coping with its effects. Farmers can no longer rely on historical averages for rainfall and temperature, and the more frequent and extreme weather events, such as droughts and floods, can spell disaster. And there are new threats, such as sea level rise and the impact of melting glaciers on water supply. How significant are small farms ? As many as two billion people worldwide depend on them for their food and livelihood. Small-holder farmers in India produce 41 percent of the country’s food grains, and other food items that contribute to local and national food security.
What is the most logical and rational corollary to the above passage ?
Answer (a) & explanation
The corollary is that supporting small farmers is part of any sustainable development agenda (a). Step 1: the passage says small farmers feed about two billion people, yet they face climate shocks first. So helping them is central to sustainable growth. That is (a). Step 2: option (d) says only small farmers can ensure food security. But they grow 41% of India's grain, not all of it. So "only" fails. Step 3: option (b), poor countries have little role in fighting warming, is not supported. Option (c), India will have no food problem, contradicts the passage's warning.
Tip: an "only" option needs the passage to say "all". A 41% share is large but not the whole.
Answer as per the official UPSC answer key.
Suppose you have sufficient amount of rupee currency in three denominations : ₹ 1, ₹ 10 and ₹ 50. In how many different ways can you pay a bill of ₹ 107 ?
Answer (c) & explanation
There are 18 ways to pay ₹ 107 (c). Step 1: count by the number of ₹ 50 notes. Two ₹ 50 notes leave ₹ 7, which can only be paid in ₹ 1 coins: 1 way. Step 2: one ₹ 50 note leaves ₹ 57. You can use 0 to 5 ₹ 10 notes, with ₹ 1 coins for the rest: 6 ways. Step 3: no ₹ 50 note leaves ₹ 107. You can use 0 to 10 ₹ 10 notes: 11 ways. Total = 1 + 6 + 11 = 18. Options (a), (b) and (d) miss or add a case.
Tip: in coin-counting questions, fix the biggest note first, then count the choices for the next one. The smallest coin always fills the rest in exactly one way.
Answer as per the official UPSC answer key.
Read the passage
Education plays a great transformatory role in life, particularly so in this rapidly changing and globalizing world. Universities are the custodians of the intellectual capital and promoters of culture and specialized knowledge. Culture is an activity of thought, and receptiveness to beauty and human feelings. A merely well informed man is only a bore on God’s earth. What we should aim at is producing men who possess both culture and expert knowledge. Their expert knowledge will give them a firm ground to start from and their culture will lead them as deep as philosophy and as high as art. Together it will impart meaning to human existence.
On the basis of the above passage, the following assumptions have been made :
- 1. A society without well educated people cannot be transformed into a modern society.
- 2. Without acquiring culture, a person’s education is not complete.
Which of the above assumptions is/are valid ?
Answer (b) & explanation
Only assumption 2 is valid (b). Step 1: the passage says "a merely well informed man is only a bore" and that education must give "both culture and expert knowledge". So education without culture is incomplete. Assumption 2 holds. Step 2: assumption 1 says a society cannot be transformed without well-educated people. The passage talks about what good education is, not about how societies modernise. "Cannot" is too absolute and not argued. Step 3: so options (a), (c) and (d) fail.
Tip: this passage echoes the thinker A. N. Whitehead. In CSAT, quoted lines are the best evidence; pick the assumption that rests directly on them.
Answer as per the official UPSC answer key.
Seeta and Geeta go for a swim after a gap of every 2 days and every 3 days respectively. If on 1st January both of them went for a swim together, when will they go together next?
Answer (d) & explanation
They swim together next on 13th January (d). Step 1: a gap of 2 days means Seeta swims on day 1, rests 2 days, then swims on day 4, so every 3rd day. A gap of 3 days means Geeta swims every 4th day. Step 2: they meet again after LCM(3, 4) = 12 days. Step 3: 1st January + 12 days = 13th January. Option (a), 7th January, uses LCM(2, 3) = 6. Options (b) and (c) also misread the gap.
Tip: "after a gap of n days" means the event repeats every n + 1 days. This wording trap appears often in CSAT calendar sums.
LCM(2, 3) = 6 gives 7 January. The gap is not the cycle.
Answer as per the official UPSC answer key.
Read the passage
Food varieties extinction is happening all over the world — and it is happening fast. For example, of the 7,000 apple varieties that were grown during the nineteenth century, fewer than a hundred remain. In the Philippines, thousands of varieties of rice once thrived; now only up to a hundred are grown there. In China, 90 percent of the wheat varieties cultivated just a century ago have disappeared. Farmers in the past painstakingly bred and developed crops well suited to the peculiarities of their local climate and environment. In the recent past, our heavy dependence on a few high yielding varieties and technology-driven production and distribution of food is causing the dwindling of diversity in food crops. If some mutating crop disease or future climate change decimates the few crop plants we have come to depend on to feed our growing population, we might desperately need some of those varieties we have let go extinct.
On the basis of the above passage, the following assumptions have been made :
- 1. Humans have been the main reason for the large scale extinction of plant species.
- 2. Consumption of food mainly from locally cultivated crops ensures crop diversity.
- 3. The present style of production and distribution of food will finally lead to the problem of food scarcity in the near future.
- 4. Our food security may depend on our ability to preserve the locally cultivated varieties of crops.
Which of the above assumptions are valid ?
Answer (b) & explanation
Assumptions 2 and 4 are valid (b). Step 1: the passage says growing local varieties keeps crop diversity alive. So eating mainly local crops supports diversity (2). Step 2: it says we "might desperately need" these varieties in future. So food security may depend on saving them (4). Step 3: assumption 1 is about all plant species, but the passage covers only food crops. Assumption 3 is a firm forecast of scarcity ("will finally lead"), which the passage does not make. So options (a), (c) and (d) fail.
Tip: "may depend" matches "might need". A cautious passage supports cautious statements, not firm predictions. India's seed banks and traditional seed savers help protect such varieties.
Answer as per the official UPSC answer key.
The number of parallelograms that can be formed from a set of four parallel lines intersecting another set of four parallel lines, is
Answer (d) & explanation
36 parallelograms can be formed (d). Step 1: a parallelogram needs 2 lines from the first set and 2 lines from the second set. Step 2: ways to choose 2 lines from 4: (1, 2), (1, 3), (1, 4), (2, 3), (2, 4), (3, 4) = 6. This is 4C2. Step 3: each choice from the first set can pair with each choice from the second: 6 × 6 = 36. Option (b), 24, and option (c), 32, miscount. Option (a), 18, halves the answer for no reason.
Tip: for m parallel lines crossing n parallel lines, parallelograms = mC2 × nC2. The formula nC2 = n(n − 1) ÷ 2 gives 4 × 3 ÷ 2 = 6.
Answer as per the official UPSC answer key.
Read the passage
A vast majority of Indians are poor, with barely 10 percent employed in the organised sector. We are being convinced that vigorous economic growth is generating substantial employment. But this is not so. When our economy was growing at 3 percent per year, employment in the organised sector was growing at 2 percent per year. As the economy began to grow at 7 — 8 percent per year, the rate of growth of employment in the organised sector actually declined to 1 percent per year.
The above passage seems to imply that
- 1. most of modern economic growth is based on technological progress.
- 2. much of modern Indian economy does not nurture sufficient symbiotic relationship with labour-intensive, natural resource-based livelihoods.
- 3. service sector in India is not very labour-intensive.
- 4. literate rural population is not willing to enter organised sector.
Which of the statements given above are correct ?
Answer (c) & explanation
Statements 1, 2 and 3 are implied (c). Step 1: the passage says India's growth has been faster but has made fewer jobs. UPSC's key reads this as growth driven by technology and capital (1). Step 2: it also implies the modern economy is cut off from labour-intensive, natural resource-based livelihoods like farming and crafts (2). And the fast-growing services sector does not use much labour (3). Step 3: statement 4 says literate rural people are unwilling to join the organised sector. Nothing in the passage blames workers' attitude. So options (a), (b) and (d) fail.
Tip: "jobless growth" is the theme here. Statements about people's motives need direct support in the passage.
Answer as per the official UPSC answer key.
Six students A, B, C, D, E and F appeared in several tests. Either C or F scores the highest. Whenever C scores the highest, then E scores the least. Whenever F scores the highest, B scores the least. In all the tests they got different marks; D scores higher than A, but they are close competitors; A scores higher than B; C scores higher than A.
If E is ranked third, then which one of the following is correct ?
Answer (b) & explanation
C gets more marks than E (b). Step 1: E is 3rd, so E is not last. So C is not first (since C first would make E last). So F is first and B is last. Step 2: C, D and A take places 2, 4 and 5. D must be just above A (close competitors). So D is 4th, A is 5th and C is 2nd. Step 3: C (2nd) is above E (3rd), so C gets more marks. Option (a) reverses this. Option (c), A fourth, and option (d), D fifth, are wrong.
Tip: use each "whenever" rule in reverse too: if E is not last, C cannot be first. Contrapositives unlock many ranking puzzles.
'close competitors' means next to each other in rank. Without it, D could be second.
Answer as per the official UPSC answer key.
Read the passage
The rural poor across the world, including India, have contributed little to human-induced climate change, yet they are on the frontline in coping with its effects. Farmers can no longer rely on historical averages for rainfall and temperature, and the more frequent and extreme weather events, such as droughts and floods, can spell disaster. And there are new threats, such as sea level rise and the impact of melting glaciers on water supply. How significant are small farms ? As many as two billion people worldwide depend on them for their food and livelihood. Small-holder farmers in India produce 41 percent of the country’s food grains, and other food items that contribute to local and national food security.
The above passage implies that
- 1. There is a potential problem of food insecurity in India.
- 2. India will have to strengthen its disaster management capabilities.
Which of the above assumptions is/are valid ?
Answer (c) & explanation
Both implications are valid (c). Step 1: the passage says climate shocks hit small farmers, who grow 41% of India's grain. If their output falls, food supply is at risk. So India faces a potential food insecurity problem. Statement 1 holds. Step 2: it says "droughts and floods can spell disaster". To handle such shocks, India must be ready with disaster management. Statement 2 holds. Step 3: so options (a), (b) and (d) fail.
Tip: "potential" and "will have to strengthen" are moderate claims that a warning passage can support. India's National Disaster Management Authority, set up under the Disaster Management Act, 2005, leads such preparedness.
Answer as per the official UPSC answer key.
'A' started from his house and walked 20 m towards East, where his friend 'B' joined him. They together walked 10 m in the same direction. Then 'A' turned left while 'B' turned right and travelled 2 m and 8 m respectively. Again 'B' turned left to travel 4 m followed by 5 m to his right to reach his office. 'A' turned right and travelled 12 m to reach his office. What is the shortest distance between the two offices ?
Answer (b) & explanation
1. Draw it. Both reach a point 30 m east of A's house.
2. A: 2 m north, then 12 m east. B: 8 m south, 4 m east, then 5 m south.
3. Gap east–west: A went 12 m east, B 4 m east: 8 m. Gap north–south: A is 2 m north, B is 13 m south: 15 m.
4. 8 and 15 make a right-angled triangle: 8 × 8 + 15 × 15 = 64 + 225 = 289 = 17 × 17. Distance = 17 m.
Answer as per the official UPSC answer key.
Read the passage
Soil, in which nearly all our food grows, is a living resource that takes years to form. Yet it can vanish in minutes. Each year 75 billion tonnes of fertile soil is lost to erosion. That is alarming — and not just for food producers. Soil can trap huge quantities of carbon dioxide in the form of organic carbon and prevent it from escaping into the atmosphere.
On the basis of the above passage, the following assumptions have been made :
- 1. Large scale soil erosion is a major reason for widespread food insecurity in the world.
- 2. Soil erosion is mainly anthropogenic.
- 3. Sustainable management of soils helps in combating climate change.
Which of the above assumptions is/are valid ?
Answer (b) & explanation
Only assumption 3 is valid (b). Step 1: the passage says soil traps carbon dioxide as organic carbon. Keeping soils healthy keeps this carbon out of the air. So sustainable soil care helps fight climate change. Assumption 3 holds. Step 2: assumption 2 says erosion is mainly anthropogenic (man-made). The passage names no cause of erosion, so 2 fails. Step 3: assumption 1 says erosion is a major reason for present food insecurity worldwide. The passage claims no such current crisis. So 1 fails, and options (a), (c) and (d) fail.
Tip: soil is the largest land store of carbon, holding more than plants and the air together. That is why soil health is a climate topic.
Answer as per the official UPSC answer key.
X, Y and Z are three contestants in a race of 1000 m. Assume that all run with different uniform speeds. X gives Y a start of 40 m and X gives Z a start of 64 m. If Y and Z were to compete in a race of 1000 m, how many metres start will Y give to Z?
Answer (b) & explanation
Y will give Z a start of 25 m (b). Step 1: X gives Y a 40 m start, so while X runs 1000 m, Y runs 960 m. X gives Z a 64 m start, so in the same time Z runs 936 m. Step 2: so Z : Y = 936 : 960 = 39 : 40. Step 3: when Y runs 1000 m, Z runs 1000 × 39/40 = 975 m. So Y can give Z a start of 1000 − 975 = 25 m. Options (a), (c) and (d) do not fit.
Tip: do not just subtract the two starts (64 − 40 = 24). Speeds are in ratio, so rescale to the new race length.
64 – 40 = 24 is close but wrong. The base is Y's 960 m, not 1000 m.
Answer as per the official UPSC answer key.
If every alternative letter of the English alphabet from B onwards (including B) is written in lower case (small letters) and the remaining letters are capitalized, then how is the first month of the second half of the year written ?
Answer (d) & explanation
July is written jUlY (d). Step 1: from B onwards, every alternate letter, B, D, F, H and so on, is written small. These are the letters at even places in the alphabet (B = 2, D = 4). The odd-place letters stay capital. Step 2: the first month of the second half of the year is JULY. Step 3: J is the 10th letter (even) → j. U is 21st (odd) → U. L is 12th (even) → l. Y is 25th (odd) → Y. So it is jUlY. Options (a), (b) and (c) get at least one letter wrong.
Tip: memorise letter positions with "EJOTY": E = 5, J = 10, O = 15, T = 20, Y = 25. It speeds up all alphabet questions.
Answer as per the official UPSC answer key.
In a school every student is assigned a unique identification number. A student is a football player if and only if the identification number is divisible by 4, whereas a student is a cricketer if and only if the identification number is divisible by 6. If every number from 1 to 100 is assigned to a student, then how many of them play cricket as well as football?
Answer (b) & explanation
8 students play both cricket and football (b). Step 1: a number divisible by both 4 and 6 must be divisible by their LCM, which is 12. It is not 24, because 4 and 6 share the factor 2. Step 2: multiples of 12 up to 100 are 12, 24, 36, 48, 60, 72, 84 and 96. Step 3: that is 8 numbers (100 ÷ 12 = 8, ignoring the remainder). Option (a), 4, uses 24 instead of 12. Options (c) and (d) are wrong.
Tip: "divisible by both" means divisible by the LCM, not the product. LCM of 4 and 6 is 12; multiplying them gives 24, which misses numbers like 12, 36 and 60.
multiplying 4 × 6 = 24 gives 4, a trap option. Use the LCM.
Answer as per the official UPSC answer key.
Read the passage
India has banking correspondents, who help bring people in the hinterland into the banking fold. For them to succeed, banks cannot crimp on costs. They also cannot afford to ignore investing in financial education and literacy. Banking correspondents are way too small to be viewed as a systemic risk. Yet India’s banking regulator has restricted them to serving only one bank, perhaps to prevent arbitrage. Efforts at banking outreach may succeed only if there are better incentives at work for such last-mile workers and also those providers who ensure not just basic bank accounts but also products such as accident and life insurance and micro pension schemes.
Which one of the following is the most logical, rational and crucial inference that can be derived from the above passage ?
Answer (c) & explanation
The inference is that meaningful financial inclusion needs banking correspondents with diverse skills (c). Step 1: the passage says correspondents must give financial education and sell insurance and pensions, not just open accounts. That needs varied skills. That is (c). Step 2: option (b) asks for more correspondents. The passage asks for better incentives, not more workers. Step 3: option (a) says efforts have failed, which the passage does not say. Option (d), each correspondent serving many banks, goes beyond the passage, and "impossible unless" is extreme.
Tip: banking correspondents are local agents who offer bank services in villages without branches. They were key to Jan Dhan Yojana, launched in 2014.
Answer as per the official UPSC answer key.
Read the following statements S1 and S2 and answer the item that follows :
S1 : Twice the weight of Sohan is less than the weight of Mohan or that of Rohan.
S2 : Twice the weight of Rohan is greater than the weight of Mohan or that of Sohan.
Which one of the following statements is correct ?
Answer (d) & explanation
Whose weight is greatest cannot be determined (d). Step 1: S1 says 2S < M and 2S < R. So Sohan is lighter than half of each of the others. Sohan is the lightest. Step 2: S2 says 2R > M and 2R > S. This tells us R is more than half of M. But M could be above or below R. Step 3: for example, M = 10, R = 8 fits, and so does M = 8, R = 10. So we cannot tell who is heaviest. Options (a), (b) and (c) fail.
Tip: "twice R is greater than M" does not mean R is greater than M. Test two sets of numbers to see whether an order is fixed.
Answer as per the official UPSC answer key.
Read the passage
A changing climate, and the eventual efforts of governments (however reluctant) to deal with it, could have a big impact on investors’ returns. Companies that produce or use large amounts of fossil fuels will face higher taxes and regulatory burdens. Some energy producers may find it impossible to exploit their known reserves, and be left with “stranded assets” — deposits of oil and coal that have to be left in the ground. Other industries could be affected by the economic damage caused by more extreme weather — storms, floods, heat waves and droughts.
On the basis of the above passage, the following assumptions have been made :
- 1. Governments and companies need to be adequately prepared to face the climate change.
- 2. Extreme weather events will reduce the economic growth of governments and companies in future.
- 3. Ignoring climate change is a huge risk for investors.
Which of the above assumptions is/are valid ?
Answer (c) & explanation
Assumptions 1 and 3 are valid (c). Step 1: the passage lists carbon taxes, stranded assets (like coal plants that lose value) and weather damage as threats to investors' returns. So ignoring climate change is a big risk for investors (3). Step 2: since these risks are real, governments and companies must be prepared (1). Step 3: assumption 2 says extreme weather will reduce growth. The passage only says it "could". So 2 is too certain. Options (a), (b) and (d) fail.
Tip: "could" in a passage does not support "will" in an option. Matching the degree of certainty is a common CSAT test.
Answer as per the official UPSC answer key.
Consider two statements S1 and S2 followed by a question :
S1 : p and q both are prime numbers.
S2 : p + q is an odd integer.
Question : Is pq an odd integer?
Which one of the following is correct?
Answer (b) & explanation
S2 alone is sufficient (b). Step 1: test S1. p and q are primes. p = 3, q = 5 gives pq = 15, odd. But p = 2, q = 3 gives pq = 6, even. So S1 gives no fixed answer. Step 2: test S2. p + q is odd. For whole numbers, an odd sum means one number is even and the other odd. Any product with an even number is even. So pq is never odd. Step 3: S2 gives a definite answer: "No". That counts as sufficient. Options (a), (c) and (d) fail.
Tip: in data sufficiency, a firm "No" is as good as a firm "Yes". Remember: even × anything = even; odd + odd = even.
a firm No is also an answer. Sufficiency does not need a "Yes".
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Answer as per the official UPSC answer key.
Read the passage
Inequality is visible, even statistically measurable in many instances, but the economic power that drives it is invisible and not measurable. Like the force of gravity, power is the organising principle of inequality, be it of income, or wealth, gender, race, religion and region. Its effects are seen in a pervasive manner in all spheres, but the ways in which economic power pulls and tilts visible economic variables remain invisibly obscure.
On the basis of the above passage, the following assumptions have been made :
- 1. Economic power is the only reason for the existence of inequality in a society.
- 2. Inequality of different kinds, income, wealth, etc. reinforces power.
- 3. Economic power can be analysed more through its effects than by direct empirical methods.
Which of the above assumptions is/are valid ?
Answer (b) & explanation
Only assumption 3 is valid (b). Step 1: the passage says economic power is "invisible and not measurable", yet its effects are seen everywhere. So we study power through its effects. Assumption 3 holds. Step 2: assumption 1 calls economic power the only reason for inequality. The passage does not say "only", so 1 overstates. Step 3: assumption 2 says inequality reinforces power. But the passage runs the other way: power drives inequality. So 2 reverses the direction. Options (a), (c) and (d) fail.
Tip: watch the direction of cause and effect. "A causes B" is not the same as "B causes A", and CSAT often flips them to set a trap.
Answer as per the official UPSC answer key.