CSAT Paper II of the 2017 Preliminary examination, held on 18 June 2017. 80 questions · 200 marks · qualifying at 33%. The questions broke down as Comprehension 36, Basic Numeracy 18, Logical Reasoning 16, Mental Ability 9.
The answer under each question is UPSC's official key. The note beside it is the first line of our explanation; the full reasoning, option by option, is one click away.
What does the above passage imply?
UPSC's answer: (c) — The passage states that climate change causes or amplifies events that hasten the reduction of resources. It explicitly links this reduction to competition over diminishing resources, which ensues in the form of political or violent conflict.
The keynote that seems to be emerging from the passage is that
UPSC's answer: (a) — The passage contrasts ineffective behaviors (hesitation, fluctuating opinions) with the specific sequence required for success: consulting wisely, resolving firmly, and executing with perseverance.
Which among the following is the most crucial message conveyed by the above passage?
UPSC's answer: (d) — The passage states that summer sea ice is melting earlier and faster, while winter freeze is coming later, indicating a lengthening melt period. It notes that summer ice extent has declined by about 30 per cent in the last three decades.
Which among the following is the most crucial message conveyed by the above passage?
UPSC's answer: (b) — The passage identifies two critical barriers to toilet adoption: ideas of purity/pollution and the fear of pits/septic tanks filling up. It states that to eradicate open defecation, these specific issues must be confronted and dealt with properly.
Which of the following is the most crucial inference from the above passage?
UPSC's answer: (b) — The passage states that while global GDP increased by 50% in the last two decades, inclusive wealth grew by only 6%. It explicitly mentions that GDP-driven economic performance has harmed inclusive wealth, specifically reducing natural capital by 30% and limiting human capital growth to 8%.
Which of the following is the most rational inference from the above passage?
UPSC's answer: (b) — The passage states that 93% of India's labour force is in the unorganized sector and employment growth has slowed to 0.5% CAGR. It explicitly links labour reforms to the potential for unlocking double-digit growth in India.
The main idea of the passage is that
UPSC's answer: (a) — The passage opens by stating that complete freedom from the obligation to work is 'unnatural' and 'ought to be illegal'. It argues that escaping one's share of work only shifts the burden to others, implying work is a collective necessity.
The author suggests that habits
UPSC's answer: (c) — The passage states that habits 'simplify the mechanism of life,' which directly implies they reduce complexity and effort in daily activities. It further explains that habits allow us to perform a multitude of things 'automatically,' preventing the need for fresh and original thought each time.
With reference to the above information, which one among the following statements must be true?
UPSC's answer: (b) — The passage states that 'some' supporters of Party X who knew Z and supported his strategy had friends in Party Y. The term 'some' implies that there is at least one individual in the group of Party X supporters who fits this description.
With reference to the above information, consider the following statements : 1. Some supporters of ‘party X’ knew Z. 2. Some supporters of ‘party X’, who opposed Z's campaign strategy, knew Z. 3. No supporters of ‘party X’ supported Z's campaign strategy. Which of the statements given above is/are not correct?
UPSC's answer: (c) — The given information says that the 'party X' supporters who knew Z and supported his campaign strategy did not agree to the alliance, and that some of them had friends in 'party Y'. So such supporters exist. Statement 1 ("some supporters of party X knew Z") is therefore true.
If second and fourth Saturdays and all the Sundays are taken as only holidays for an office, what would be the minimum number of possible working days of any month of any year?
UPSC's answer: (b) — Every month has at least 28 days, which guarantees at least 4 Saturdays and 4 Sundays, so the 2nd and 4th Saturdays always exist as holidays regardless of the month's length or starting day.
If there is a policy that 1/3rd of a population of a community has migrated every year from one place to some other place, what is the leftover population of that community after the sixth year, if there is no further growth in the population during this period?
UPSC's answer: (d) — Each year one-third of the remaining population leaves, so two-thirds stays. After six years the fraction left is (2/3) multiplied by itself six times: 2⁶/3⁶ = 64/729. So 64/729 of the population remains, option (d).
Four tests—Physics, Chemistry, Mathematics and Biology are to be conducted on four consecutive days, not necessarily in the same order. The Physics test is held before the test which is conducted after Biology. Chemistry is conducted exactly after two tests are held. Which is the last test held?
UPSC's answer: (c) — Let the four consecutive days be Day 1, Day 2, Day 3, and Day 4. The condition 'Chemistry is conducted exactly after two tests are held' means Chemistry is on Day 3 (since two tests precede it).
The sum of income of A and B is more than that of C and D taken together. The sum of income of A and C is the same as that of B and D taken together. Moreover, A earns half as much as the sum of the income of B and D. Whose income is the highest?
UPSC's answer: (b) — Write the incomes as A, B, C and D. "A earns half as much as B and D together" gives B + D = 2A. "A + C equals B + D" then gives A + C = 2A, so C = A. "A + B is more than C + D" becomes A + B > A + D, so B > D.
Consider the following : Statement : Good voice is a natural gift but one has to keep practising to improve and excel well in the field of music. Conclusions : I. Natural gifts need nurturing and care. II. Even though one's voice is not good, one can keep practising. Which one of the following is correct in respect of the above statement and conclusions?
UPSC's answer: (a) — The statement asserts that a good voice is a natural gift, but improvement and excellence require continuous practice. Conclusion I states that natural gifts need nurturing and care, which is a direct logical inference from the requirement of practice to improve a natural gift.
There are three pillars X, Y and Z of different heights. Three spiders A, B and C start to climb on these pillars simultaneously. In one chance, A climbs on X by 6 cm but slips down 1 cm. B climbs on Y by 7 cm but slips down 3 cm. C climbs on Z by 6·5 cm but slips down 2 cm. If each of them requires 40 chances to reach the top of the pillars, what is the height of the shortest pillar?
UPSC's answer: (b) — A's net gain per chance is 6 cm - 1 cm = 5 cm, but on the 40th chance it reaches the top before slipping. So pillar X height = 39 × 5 cm + 6 cm = 195 cm + 6 cm = 201 cm. B's net gain per chance is 7 cm - 3 cm = 4 cm, with the 40th chance adding 7 cm.
“Rights are certain advantageous conditions of social well-being indispensable to the true development of the citizen.” In the light of this statement, which one of the following is the correct understanding of rights?
UPSC's answer: (c) — The statement explicitly defines rights as 'advantageous conditions of social well-being,' directly linking them to the collective benefit of society.
15 students failed in a class of 52. After removing the names of failed students, a merit order list has been prepared in which the position of Ramesh is 22ⁿᵈ from the top. What is his position from the bottom?
UPSC's answer: (c) — Total students in the class are 52. 15 students failed, so the number of students in the merit list is 52 - 15 = 37. Ramesh's position from the top in this merit list is 22nd. To find his position from the bottom, use the formula: (Total in list - Position from top) + 1.
Consider the following : A + B means A is the son of B. A – B means A is the wife of B. What does the expression P + R – Q mean?
UPSC's answer: (c) — The expression is P + R - Q, which must be evaluated from left to right based on the given definitions. First, 'P + R' means P is the son of R, establishing that R is the parent of P. Next, 'R - Q' means R is the wife of Q, establishing that Q is the husband of R.
Gopal bought a cell phone and sold it to Ram at 10% profit. Then Ram wanted to sell it back to Gopal at 10% loss. What will be Gopal's position if he agreed?
UPSC's answer: (c) — Let the original cost price (CP) of the phone for Gopal be 100. Gopal sells it to Ram at a 10% profit, so the selling price (SP) for Gopal (and CP for Ram) is 100 + 10 = 110. Ram sells it back to Gopal at a 10% loss on his cost price of 110.
The challenge the author of the above passage throws to the public is to achieve
UPSC's answer: (d) — The passage opens by stating, 'We have hard work ahead,' directly identifying hard work as the primary challenge for the public. It emphasizes that all citizens, regardless of religion, are 'equally the children of India,' which establishes the foundation for brotherhood.
In the light of the above passage, the nature of General Will is best described as
UPSC's answer: (c) — The passage states that individuals put their person and power in common under the 'supreme direction of the General Will'.
What does the above passage imply?
UPSC's answer: (d) — The passage states that in a democratic state with high political maturity, the conflict between the sovereign law-making body and the organized will of the people 'seldom occurs'.
This passage relates to
UPSC's answer: (a) — The passage explicitly states that a successful democracy depends on widespread interest and participation, with voting as an essential part.
The passage seems to suggest that
UPSC's answer: (d) — The passage contrasts leaders in free countries, who are selected for outstanding character and ability, with dictators who often rise to power through chance or the 'unhappy state' of their country. The phrase 'unhappy state of his country' is synonymous with despair, instability, or crisis.
With reference to the above passage, the following assumptions have been made : 1. People always see the leisure time as a gift and use it for acquiring more material possessions. 2. Use of leisure by some people to produce new and original things has been the chief source of human progress. Which of these assumptions is/are valid?
UPSC's answer: (b) — The passage explicitly states that the 'creative use of leisure by a minority' has been the 'mainspring of all human progress beyond the primitive level,' which directly validates Assumption 2.
With reference to the above passage, the following assumptions have been made : 1. A study of the famous battles of history would help us understand the modern warfare. 2. Studying the history is essential for anyone who aspires to be a leader. Which of these assumptions is/are valid?
UPSC's answer: (d) — The passage states that studying famous battles reveals qualities and attributes that enabled winners to win, specifically for those who lead or aspire to leadership.
Suppose the average weight of 9 persons is 50 kg. The average weight of the first 5 persons is 45 kg, whereas the average weight of the last 5 persons is 55 kg. Then the weight of the 5ᵗʰ person will be
UPSC's answer: (c) — The total weight of all 9 persons is calculated as 9 multiplied by the average weight of 50 kg, which equals 450 kg. The total weight of the first 5 persons is 5 multiplied by their average weight of 45 kg, resulting in 225 kg.
In a group of six women, there are four tennis players, four postgraduates in Sociology, one postgraduate in Commerce and three bank employees. Vimala and Kamla are the bank employees while Amala and Komala are unemployed. Komala and Nirmala are among the tennis players. Amala, Kamla, Komala and Nirmala are postgraduates in Sociology of whom two are bank employees. If Shyamala is a postgraduate in Commerce, who among the following is both a tennis player and a bank employee?
UPSC's answer: (c) — The four Sociology postgraduates are Amala, Kamla, Komala and Nirmala, and two of them are bank employees. Amala and Komala are unemployed, so the two bank employees among them are Kamla and Nirmala. Nirmala is also one of the tennis players.
P = (40% of A) + (65% of B) and Q = (50% of A) + (50% of B), where A is greater than B. In this context, which of the following statements is correct?
UPSC's answer: (d) — Let A = 100 and B = 0 (satisfying A > B). Then P = 40 + 0 = 40 and Q = 50 + 0 = 50, so Q > P. Let A = 100 and B = 99 (satisfying A > B). Then P = 40 + 64.35 = 104.35 and Q = 50 + 49.5 = 99.5, so P > Q.
A watch loses 2 minutes in every 24 hours while another watch gains 2 minutes in every 24 hours. At a particular instant, the two watches showed an identical time. Which of the following statements is correct if 24-hour clock is followed?
UPSC's answer: (d) — One watch loses 2 minutes a day and the other gains 2 minutes a day, so the gap between them grows by 4 minutes a day. On a 24-hour clock they show the same time again only when the gap reaches 24 hours = 1,440 minutes. That takes 1,440 ÷ 4 = 360 days.
In a city, 12% of households earn less than ₹ 30,000 per year, 6% households earn more than ₹ 2,00,000 per year, 22% households earn more than ₹ 1,00,000 per year and 990 households earn between ₹ 30,000 and ₹ 1,00,000 per year. How many households earn between ₹ 1,00,000 and ₹ 2,00,000 per year?
UPSC's answer: (b) — Let the total number of households be T. The percentage of households earning between ₹30,000 and ₹1,00,000 is calculated by subtracting the percentage earning less than ₹30,000 (12%) from the percentage earning less than or equal to ₹1,00,000 (100% - 22% = 78%), resulting in 78% - 12% = 66%.
A clock strikes once at 1 o’clock, twice at 2 o’clock and thrice at 3 o’clock, and so on. If it takes 12 seconds to strike at 5 o’clock, what is the time taken by it to strike at 10 o’clock?
UPSC's answer: (b) — UPSC's official answer is (b) 24 seconds, obtained by treating the striking time as proportional to the number of strikes: 5 strikes take 12 seconds, so 10 strikes take 12 × 10/5 = 24 seconds.
Consider the given statement and the two conclusions that follow : Statement : Morning walk is good for health. Conclusions : 1. All healthy people go for morning walk. 2. Morning walk is essential for maintaining good health. What is/are the valid conclusion/conclusions?
UPSC's answer: (d) — The statement 'Morning walk is good for health' establishes that morning walking is a beneficial activity, but it does not imply it is the only way to maintain health or that it is mandatory.
There are thirteen 2-digit consecutive odd numbers. If 39 is the mean of the first five such numbers, then what is the mean of all the thirteen numbers?
UPSC's answer: (a) — Thirteen consecutive odd numbers form an arithmetic sequence with common difference 2: a, a+2, a+4, …, a+24. The first five terms are a, a+2, a+4, a+6, a+8, and their mean is (5a + 20)/5 = a + 4.
Six boys A, B, C, D, E and F play a game of cards. Each has a pack of 10 cards. F borrows 2 cards from A and gives away 5 to C who in turn gives 3 to B while B gives 6 to D who passes on 1 to E. Then the number of cards possessed by D and E is equal to the number of cards possessed by
UPSC's answer: (b) — Everyone starts with 10 cards. F borrows 2 from A: A 8, F 12. F gives 5 to C: F 7, C 15. C gives 3 to B: C 12, B 13. B gives 6 to D: B 7, D 16. D gives 1 to E: D 15, E 11. D + E = 15 + 11 = 26. B + C + F = 7 + 12 + 7 = 26, option (b).
There is a milk sample with 50% water in it. If 1/3ʳᵈ of this milk is added to equal amount of pure milk, then water in the new mixture will fall down to
UPSC's answer: (a) — Let the initial volume of the milk sample be 3 units, which contains 1.5 units of water (50%) and 1.5 units of milk. One-third of this sample is taken, which equals 1 unit of the mixture. This 1 unit contains 0.5 units of water and 0.5 units of milk.
There are 4 horizontal and 4 vertical lines, parallel and equidistant to one another on a board. What is the maximum number of rectangles and squares that can be formed?
UPSC's answer: (c) — A grid formed by 4 horizontal and 4 vertical lines creates a 3x3 array of unit cells, resulting in 9 small squares. To form a rectangle or square, one must choose any 2 distinct horizontal lines and any 2 distinct vertical lines from the available sets.
A freight train left Delhi for Mumbai at an average speed of 40 km/hr. Two hours later, an express train left Delhi for Mumbai, following the freight train on a parallel track at an average speed of 60 km/hr. How far from Delhi would the express train meet the freight train?
UPSC's answer: (c) — The freight train has a 2-hour head start at 40 km/hr, covering 80 km before the express train departs. The relative speed between the express train (60 km/hr) and the freight train (40 km/hr) is 20 km/hr. The time required for the express train to close the 80 km gap is 80 km / 20 km/hr = 4 hours.
In a test, Randhir obtained more marks than the total marks obtained by Kunal and Debu. The total marks obtained by Kunal and Shankar are more than those of Randhir. Sonal obtained more marks than Shankar. Neha obtained more marks than Randhir. Who amongst them obtained highest marks?
UPSC's answer: (d) — From the first two statements, Kunal + Debu < Randhir < Kunal + Shankar, so Shankar > Debu. Neha > Randhir and Sonal > Shankar. Nothing fixes Sonal against Neha.
Which one of the following is the best explanation of the above passage?
UPSC's answer: (a) — The passage states that political development disrupts traditional institutions, leading to a mix of renewed traditional identifications and new alignments. It highlights that this process involves both the decay of old loyalties and the growth of new group awarenesses (class, tribe, region, etc.).
Which among the following is the most logical, rational and critical inference that can be made from the above passage?
UPSC's answer: (c) — The passage defines political legitimacy as a 'mass demand from below' that creates the necessary political force for decentralization to succeed.
Which among the following is the most logical and essential message conveyed by the above passage?
UPSC's answer: (b) — The passage states that the digital is not just a tool for specific tasks but is integral to our perception of identity and connection to the world. It emphasizes that digital technology is woven into the fabric of how we define our domains and exist in the present moment.
Which among the following is the most logical, rational and critical inference that can be made from the above passage?
UPSC's answer: (a) — The passage explicitly states that the broad, overall cause of the middle-income trap is a 'collapse in the growth of productivity'. It defines the trap as a situation where average incomes, which were growing rapidly, stop growing beyond a certain point.
Which among the following is the most logical and rational assumption that can be made from the above passage?
UPSC's answer: (c) — The passage explicitly states that an innovative India will be 'inclusive' and that innovation and R&D can 'mitigate increases in social inequality'. It further notes that the divergence in productivity between agriculture and knowledge-intensive sectors threatens to increase income inequality.
Which of the following is the most rational inference from the above passage?
UPSC's answer: (d) — The passage explicitly states that 'There are still gaps in understanding how climate change will work as the root cause of migration.' It also notes that the international community has not reached a consensus on the definition and status of climate refugees.
On the basis of the above passage, the following assumptions have been made : 1. Synthetic pesticides should never be used in modern agriculture. 2. One of the aims of sustainable agriculture is to ensure minimal ecological imbalance. 3. Botanical pesticides are more effective as compared to synthetic pesticides. Which of the assumptions given above is/are correct?
UPSC's answer: (b) — Assumption 1 is incorrect because the passage highlights the dangers of synthetic pesticides but does not state they should 'never' be used; it only suggests botanical alternatives are safer, implying a preference rather than an absolute ban.
Which of the following statements is/are correct regarding biopesticides? 1. They are not hazardous to human health. 2. They are persistent in environment. 3. They are essential to maintain the biodiversity of any ecosystem. Select the correct answer using the code given below.
UPSC's answer: (a) — Statement 1 is correct because biopesticides are derived from natural materials like animals, plants, bacteria, or minerals, making them generally non-toxic and safe for human health compared to synthetic chemicals.
Certain 3-digit numbers have the following characteristics : 1. All the three digits are different. 2. The number is divisible by 7. 3. The number on reversing the digits is also divisible by 7. How many such 3-digit numbers are there?
UPSC's answer: (b) — Let the number be 100a + 10b + c and its reverse be 100c + 10b + a; since both are divisible by 7, their difference 99(a - c) is divisible by 7.
Examine the following statements : 1. All colours are pleasant. 2. Some colours are pleasant. 3. No colour is pleasant. 4. Some colours are not pleasant. Given that statement 4 is true, what can be definitely concluded?
UPSC's answer: (d) — Statement 4 states 'Some colours are not pleasant,' which is a particular negative proposition (O-type) in categorical logic. In the traditional Square of Opposition, the O proposition is contradictory to the A proposition, which is 'All colours are pleasant' (Statement 1).
How many numbers are there between 99 and 1000 such that the digit 8 occupies the units place?
UPSC's answer: (c) — The numbers must be strictly between 99 and 1000, meaning they range from 100 to 999. These are all three-digit numbers of the form XYZ, where X is the hundreds digit, Y is the tens digit, and Z is the units digit. The condition states that the digit 8 occupies the units place, so Z is fixed as 8.
If for a sample data Mean < Median < Mode then the distribution is
UPSC's answer: (d) — In a negatively skewed distribution, the long tail extends toward lower values, pulling the mean below the median. The median lies between the mean and mode because it is less affected by extreme low values than the mean but more than the mode.
The age of Mr. X last year was the square of a number and it would be the cube of a number next year. What is the least number of years he must wait for his age to become the cube of a number again?
UPSC's answer: (b) — Let Mr. X's age last year be n² and his age next year be m³. Since these differ by 2 years, we have m³ − n² = 2, i.e., n² + 2 = m³. Testing small values of m: for m = 3, m³ = 27, so n² = 25 and n = 5. This gives last year's age = 25, current age = 26, and next year's age = 27 = 3³.
P works thrice as fast as Q, whereas P and Q together can work four times as fast as R. If P, Q and R together work on a job, in what ratio should they share the earnings?
UPSC's answer: (a) — Let the work rate of Q be 1 unit per day. Since P works thrice as fast as Q, P's rate is 3 units per day. The combined rate of P and Q is 3 + 1 = 4 units per day. The problem states that P and Q together work four times as fast as R, so 4 = 4 * (R's rate), which means R's rate is 1 unit per day.
Consider the following relationships among members of a family of six persons A, B, C, D, E and F : 1. The number of males equals that of females. 2. A and E are sons of F. 3. D is the mother of two, one boy and one girl. 4. B is the son of A. 5. There is only one married couple in the family at present. Which one of the following inferences can be drawn from the above?
UPSC's answer: (b) — A and E are sons of F and B is the son of A, so A, E and B are male. With three males and three females, C, D and F are female; F is the mother of A and E. D is the mother of a boy and a girl. The only boy not already accounted for as F's son is B, so D's children are B and C.
A bag contains 20 balls. 8 balls are green, 7 are white and 5 are red. What is the minimum number of balls that must be picked up from the bag blindfolded (without replacing any of it) to be assured of picking at least one ball of each colour?
UPSC's answer: (b) — To find the minimum number of balls needed to guarantee at least one of each color, we must consider the worst-case scenario. In the worst case, you pick all balls of the two most numerous colors before picking the first ball of the third color.
If 2 boys and 2 girls are to be arranged in a row so that the girls are not next to each other, how many possible arrangements are there?
UPSC's answer: (c) — Arrange the 2 boys first: 2 ways. This creates 3 gaps (before, between, after). Put the 2 girls into 2 different gaps so they are not next to each other: 3 × 2 = 6 ways (choosing and ordering the gaps). Total = 2 × 6 = 12, option (c).
The outer surface of a 4 cm × 4 cm × 4 cm cube is painted completely in red. It is sliced parallel to the faces to yield sixty four 1 cm × 1 cm × 1 cm small cubes. How many small cubes do not have painted faces?
UPSC's answer: (a) — The 4 cm cube is cut into 4 × 4 × 4 = 64 cubes of 1 cm. Cubes with no painted face lie in the interior, after removing the outer layer on every side. The interior block is (4 − 2) × (4 − 2) × (4 − 2) = 2 × 2 × 2 = 8 cubes, option (a).
Consider the following : A, B, C, D, E, F, G and H are standing in a row facing North. B is not neighbour of G. F is to the immediate right of G and neighbour of E. G is not at the extreme end. A is sixth to the left of E. H is sixth to the right of C. Which one of the following is correct in respect of the above?
UPSC's answer: (c) — Number the positions 1 to 8 from the left. "A is sixth to the left of E" gives (A, E) = (1, 7) or (2, 8); "H is sixth to the right of C" gives (C, H) = (1, 7) or (2, 8). These pairs cannot share positions, so one is (1, 7) and the other (2, 8).
In a certain code, ‘256’ means ‘red colour chalk’, ‘589’ means ‘green colour flower’ and ‘254’ means ‘white colour chalk’. The digit in the code that indicates ‘white’ is
UPSC's answer: (b) — '256' (red colour chalk) and '254' (white colour chalk) share 2 and 5, which stand for 'colour' and 'chalk'. The remaining digit of '256', 6, is 'red'; the remaining digit of '254', 4, is 'white'. So 'white' is 4, option (b).
Which among the following is the most logical and rational inference that can be made from the above passage?
UPSC's answer: (c) — The passage states that the AQI is most useful when pollution levels are normally low, allowing the public to take preventive action during temporary spikes. It explicitly notes that in many large Indian cities, pollution levels remain well above health standards for a large part of the year.
Which among the following is the most logical and rational inference that can be made from the above passage?
UPSC's answer: (c) — The passage states that for agricultural per capita incomes to rise, the number of people dependent on agriculture must shrink. It notes that while industry creates jobs, many are low-productivity and unorganized, offering poor protection and benefits.
Which among the following is the most logical and rational inference that can be made from the above passage?
UPSC's answer: (a) — In hurricane Mitch, farms using ecoagriculture suffered 58–99 per cent less damage than conventional farms: less vulnerability to disasters.
Which among the following is the most logical and rational inference that can be made from the above passage?
UPSC's answer: (c) — The passage states that to increase manufacturing's share in GDP to 25%, India must capture global markets in high-technology and capital-intensive sectors. It defines high-tech industries as being mainly capital and technology intensive, implying a need for significant investment in these areas.
Which among the following is the most logical corollary to the above passage?
UPSC's answer: (a) — The passage highlights a paradox: India has record agricultural production and is a top global producer, yet it still houses a quarter of the world's undernourished people.
Which one of the following views corroborates the above statement?
UPSC's answer: (b) — The metaphor compares the Centre to a thread and States to pearls, implying the Centre holds the States together. The phrase 'if the thread snaps, the pearls are scattered' indicates that without the Centre, the States would disintegrate or lose unity.
The above statement argues for
UPSC's answer: (b) — The passage explicitly states that every man living under a government must first give his own consent to be subject to it. It argues that the poorest man is not bound by a government in which he has no voice or representation.
The average rainfall in a city for the first four days was recorded to be 0·40 inch. The rainfall on the last two days was in the ratio of 4 : 3. The average of six days was 0·50 inch. What was the rainfall on the fifth day?
UPSC's answer: (c) — Calculate the total rainfall for the first four days: 4 days × 0.40 inch/day = 1.60 inches. Calculate the total rainfall for all six days: 6 days × 0.50 inch/day = 3.00 inches. Determine the combined rainfall for the last two days (5th and 6th): 3.00 - 1.60 = 1.40 inches.
Who is specialized in Geography?
UPSC's answer: (a) — Fixed by the clues: C Delhi (Sociology), D Shillong, F Srinagar (Commerce), G Chennai (Statistics), A Economics. The cities left for A, B and E are Hyderabad, Kanpur and Mumbai.
To which city does the Lecturer specialized in Economics belong?
UPSC's answer: (b) — The cities left for A, B and E are Hyderabad, Kanpur and Mumbai (C Delhi, D Shillong, F Srinagar, G Chennai). A teaches Economics, so A is not the Kanpur (Geography) lecturer; clue 5 says A is not from Hyderabad. So the Economics lecturer, A, is from Mumbai, option (b).
Who of the following belongs to Hyderabad?
UPSC's answer: (b) — A is from Mumbai (see the previous items), so B and E share Hyderabad and Kanpur. B teaches neither History nor Mathematics, so B teaches the remaining subject, Geography, and is the Kanpur lecturer. So E is from Hyderabad, option (b).
In a school, there are five teachers A, B, C, D and E. A and B teach Hindi and English. C and B teach English and Geography. D and A teach Mathematics and Hindi. E and B teach History and French. Who teaches maximum number of subjects?
UPSC's answer: (b) — A and B teach Hindi and English, so A teaches Hindi and English, and B teaches Hindi and English. C and B teach English and Geography, so B adds Geography, and C teaches English and Geography. D and A teach Mathematics and Hindi, so A adds Mathematics, and D teaches Mathematics and Hindi.
A 2-digit number is reversed. The larger of the two numbers is divided by the smaller one. What is the largest possible remainder?
UPSC's answer: (d) — For a number and its reverse, the larger divided by the smaller gives the biggest remainder when the quotient is 1, and then the remainder equals their difference, 9 × (difference of the digits). The quotient stays 1 only if the larger is less than twice the smaller.
The monthly incomes of X and Y are in the ratio of 4 : 3 and their monthly expenses are in the ratio of 3 : 2. However, each saves ₹ 6,000 per month. What is their total monthly income?
UPSC's answer: (b) — Let the monthly incomes of X and Y be 4k and 3k respectively, based on the given ratio of 4:3. Let their monthly expenses be 3m and 2m respectively, based on the given ratio of 3:2. Since each saves ₹6,000, we form the equations: 4k - 3m = 6,000 and 3k - 2m = 6,000.
Two walls and a ceiling of a room meet at right angles at a point P. A fly is in the air 1 m from one wall, 8 m from the other wall and 9 m from the point P. How many meters is the fly from the ceiling?
UPSC's answer: (a) — Take P as the corner. The fly's distances from the two walls and the ceiling are its three perpendicular coordinates, and its distance from P is the length of the diagonal. So 1² + 8² + h² = 9², that is 1 + 64 + h² = 81, giving h² = 16 and h = 4. The fly is 4 m from the ceiling, option (a).
In how many different ways can a train travel from F to A without passing through any station more than once?
UPSC's answer: (d) — From F the only way out is the two-way F–D (B to F is one-way into F). From D the train can go to H or E. Via H: H goes only to G; from G, C then A works (G to B leads back to F, already visited). Route: F–D–H–G–C–A. Via E: E–A directly; E–C–A; and E–G–C–A. Routes: F–D–E–A, F–D–E–C–A, F–D–E–G–C–A.
If the route between G and C is closed, which one of the following stations need not be passed through while travelling from H to C?
UPSC's answer: (c) — With G-C closed, from H the only outgoing passage is H to G, so every H-to-C route must start H-G. From G the only usable outgoing passage is G to B, because G-C is closed and G-B is two-way, so the route must continue G-B.
There are certain 2-digit numbers. The difference between the number and the one obtained on reversing it is always 27. How many such maximum 2-digit numbers are there?
UPSC's answer: (d) — Let the 2-digit number be 10a + b (a ∈ {1,…,9}, b ∈ {0,…,9}); its reverse is 10b + a, and the difference is (10a + b) − (10b + a) = 9(a − b). Setting |9(a − b)| = 27 gives |a − b| = 3, so either a − b = 3 or b − a = 3.
What is the total number of digits printed, if a book containing 150 pages is to be numbered from 1 to 150?
UPSC's answer: (b) — Pages 1 to 9 are single-digit numbers, contributing 9 × 1 = 9 digits. Pages 10 to 99 are two-digit numbers, contributing 90 × 2 = 180 digits. Pages 100 to 150 are three-digit numbers, contributing 51 × 3 = 153 digits.
Question paper and answer key: Union Public Service Commission. Explanations: UPSC Answer Check. Practise this paper with a timer →
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