UPSC Prelims 1997 · General Studies
Question 142: Logical Reasoning and Mental Ability
Seven persons P, Q, R, S, T, U and V participate in and finish all the events of a series of swimming races. There are no ties at the finish of any of the events. V always finishes somewhere ahead of P. P always finishes somewhere ahead of Q. Either R finishes first and T finishes last or S finishes first and U or Q finishes last. If in a particular race V finished fifth, then which one of the following would be true?
AnswerThe answer is (a).
V is fifth, V is ahead of P and P is ahead of Q, so P and Q must take sixth and seventh places, and Q is last. The first condition (R first and T last) needs T last, which is impossible since Q is last. So the second must hold: S finishes first and Q finishes last. That fixes S first, and R, T and U fill second, third and fourth in some order.
Why each option is right or wrong
- (a) Right: S must finish first.
- (b) R could be second, third or fourth, so need not be second.
- (c) T could take any of the second to fourth places.
- (d) R need not be fourth.
Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 1997, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.