UPSC Prelims 2021
Get UPSC Prelims Previous Year Question (PYQ) Papers with detailed explanations, mindmaps, organized year-wise and subject-wise for CSAT.
- ReasoningView Answer for: 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?
There are three points P, Q and R on a straight line such that . If n is the number of possible values of , then what is n equal to?
- ReasoningView Answer for: Seven books P, Q, R, S, T, U, and V are placed side by side. R, Q, and T have blue covers and other books have red covers. Only S and U are new books and the rest are old. P, R and S are law reports; the rest are Gazetteers. Books of old Gazetteers with blue covers are:
Seven books P, Q, R, S, T, U, and V are placed side by side. R, Q, and T have blue covers and other books have red covers. Only S and U are new books and the rest are old. P, R and S are law reports; the rest are Gazetteers. Books of old Gazetteers with blue covers are:
- ReasoningView Answer for: A student appeared in 6 papers. The maximum marks are the same for each paper. His marks in these papers are in the proportion $5 : 6 : 7 : 8 : 9 : 10$. Overall he scored 60%. In how many number of papers did he score less than 60% of the maximum marks?
A student appeared in 6 papers. The maximum marks are the same for each paper. His marks in these papers are in the proportion . Overall he scored 60%. In how many number of papers did he score less than 60% of the maximum marks?
- ReasoningView Answer for: Joseph visits the club on every 5th day, Harsh visits on every 24th day, while Sumit visits on every 9th day. If all three of them met at the club on a Sunday, then on which day will all three of them meet again?
Joseph visits the club on every 5th day, Harsh visits on every 24th day, while Sumit visits on every 9th day. If all three of them met at the club on a Sunday, then on which day will all three of them meet again?
- ReasoningView Answer for: A Statement followed by Conclusion-I and Conclusion-II is given below. You have to take the Statement to be true even if it seems to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statement, disregarding the commonly known facts.Statement: Some cats are almirahs. Some almirahs are chairs. All chairs are tables. Conclusion-I: Certainly some almirahs are tables. Conclusion-II: Some cats may not be chairs.Which one of the following is correct?
A Statement followed by Conclusion-I and Conclusion-II is given below. You have to take the Statement to be true even if it seems to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statement, disregarding the commonly known facts.
Statement: Some cats are almirahs. Some almirahs are chairs. All chairs are tables. Conclusion-I: Certainly some almirahs are tables. Conclusion-II: Some cats may not be chairs.
Which one of the following is correct?
- ReasoningView Answer for: Consider the following addition problem : $3P + 4P + PP + PP = RQ2$; where P, Q and R are different digits. What is the arithmetic mean of all such possible sums?
Consider the following addition problem : ; where P, Q and R are different digits. What is the arithmetic mean of all such possible sums?
- ReasoningView Answer for: A Statement followed by Conclusion-I and Conclusion-II is given below. You have to take the Statement to be true even if it seems to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statement, disregarding the commonly known facts.Statement: Some radios are mobiles. All mobiles are computers. Some computers are watches.Conclusion-I: Certainly some radios are watches. Conclusion-II: Certainly some mobiles are watches.Which one of the following is correct?
A Statement followed by Conclusion-I and Conclusion-II is given below. You have to take the Statement to be true even if it seems to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statement, disregarding the commonly known facts.
Statement: Some radios are mobiles. All mobiles are computers. Some computers are watches.
Conclusion-I: Certainly some radios are watches. Conclusion-II: Certainly some mobiles are watches.
Which one of the following is correct?
- ReasoningView Answer for: Consider two Statements and four Conclusions given below. You have to take the Statements to be true even if they seem to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statements, disregarding the commonly known facts.Statement-1: Some greens are blues. Statement-2: Some blues are blacks.Conclusion-1: Some greens are blacks. Conclusion-2: No green is black. Conclusion-3: All greens are blacks. Conclusion-4: All blacks are greens.Which one of the following is correct?
Consider two Statements and four Conclusions given below. You have to take the Statements to be true even if they seem to be at variance from the commonly known facts. Read all Conclusions and then decide which of the given Conclusion(s) logically follows/follow from the Statements, disregarding the commonly known facts.
Statement-1: Some greens are blues. Statement-2: Some blues are blacks.
Conclusion-1: Some greens are blacks. Conclusion-2: No green is black. Conclusion-3: All greens are blacks. Conclusion-4: All blacks are greens.
Which one of the following is correct?
- ReasoningView Answer for: Which day is 10th October, 2027?
Which day is 10th October, 2027?
- ReasoningView Answer for: In a code language 'MATHEMATICS' is written as 'LBSIDNZUHDR'. How is CHEMISTRY' written in that code language?
In a code language 'MATHEMATICS' is written as 'LBSIDNZUHDR'. How is CHEMISTRY' written in that code language?
- ReasoningView Answer for: Integers are listed from 700 to 1000. In how many integers is the sum of the digits 10?
Integers are listed from 700 to 1000. In how many integers is the sum of the digits 10?
- ReasoningView Answer for: Consider two Statements and a Question:Statement-1: Each of A and D is heavier than each of B, E and F, but none of them is the heaviest. Statement-2: A is heavier than D, but is lighter than C. Question: Who is the heaviest among A, B, C, D and E?Which one of the following is correct in respect of the Statements and the Question?
Consider two Statements and a Question:
Statement-1: Each of A and D is heavier than each of B, E and F, but none of them is the heaviest. Statement-2: A is heavier than D, but is lighter than C. Question: Who is the heaviest among A, B, C, D and E?
Which one of the following is correct in respect of the Statements and the Question?
- ReasoningView Answer for: Consider two Statements and a Question:Statement-1: Priya is 4 ranks below Seema and is 31st from the bottom. Statement-2: Ena is 2 ranks above Seema and is 37th from the bottom. Question: What is Seema's rank from the top in the class of 40 students?Which one of the following is correct in respect of the Statements and the Question?
Consider two Statements and a Question:
Statement-1: Priya is 4 ranks below Seema and is 31st from the bottom. Statement-2: Ena is 2 ranks above Seema and is 37th from the bottom. Question: What is Seema's rank from the top in the class of 40 students?
Which one of the following is correct in respect of the Statements and the Question?
- ReasoningView Answer for: 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?
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?
- Reasoning
Most people would agree that telling deliberate lies is wrong, except perhaps in certain special situations where more harm will be done by telling the truth. Even the most truthful people probably tell a good many more lies that might be regarded as semantic lies; their use of words contains some measure of falsehood, more or less deliberate.
View Answer for: Which one of the following habits is found more often in good people?Which one of the following habits is found more often in good people?
- ReasoningView Answer for: In the series $bababababaab$; fill in the six blanks fusing one of the following given four choices such that the series follows a specific order.
In the series _b_a_ba_b_abab_aab; fill in the six blanks fusing one of the following given four choices such that the series follows a specific order.
- ReasoningView Answer for: 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?
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?
- ReasoningView Answer for: A biology class at high school predicted that a local population of animals will double in size every 12 years. The population at the beginning of the year 2021 was estimated to be 50 animals. If P represents the population after n years, then which one of the following equations represents the model of the class for the population?
A biology class at high school predicted that a local population of animals will double in size every 12 years. The population at the beginning of the year 2021 was estimated to be 50 animals. If P represents the population after n years, then which one of the following equations represents the model of the class for the population?
- ReasoningView Answer for: Images of consonants of the English alphabet (Capitals) are observed in a mirror. What is the number of images of these which do not look like their original shapes?
Images of consonants of the English alphabet (Capitals) are observed in a mirror. What is the number of images of these which do not look like their original shapes?
- ReasoningView Answer for: Following is a matrix of certain entries. The entries follow a certain trend row-wise. Choose the missing entry (?) accordingly:Table
Following is a matrix of certain entries. The entries follow a certain trend row-wise. Choose the missing entry (?) accordingly:
- ReasoningView Answer for: In the English alphabet, the first 4 letters are written in opposite order, and the next 4 letters are written in opposite order and so on; and at the end Y and Z are interchanged. Which will be the fourth letter to the right of the 13th letter?
In the English alphabet, the first 4 letters are written in opposite order, and the next 4 letters are written in opposite order and so on; and at the end Y and Z are interchanged. Which will be the fourth letter to the right of the 13th letter?
- ReasoningView Answer for: At which one of the following times, do the hour hand and the minute hand of the clock make an angle of $180^{\circ}$ with each other?
At which one of the following times, do the hour hand and the minute hand of the clock make an angle of with each other?
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