UPSC Prelims 2018 · CSAT
Question 25: Logical Reasoning and Mental Ability
The plan of an office block for six officers A, B, C, D, E and F is as follows : Both B and C occupy offices to the right of the corridor (as one enters the office block) and A occupies on the left of the corridor. E and F occupy offices on opposite sides of the corridor but their offices do not face each other. The offices of C and D face each other. E does not have a corner office. F's office is further down the corridor than A's, but on the same side.
If E sits in his office and faces the corridor, whose office is to his left?
AnswerUPSC’s answer is (c).
Layout from the clues, entrance to end: left side D, A, F; right side C, E, B. Working: F is on A's side but further in; E is not at a corner, so E is the middle office on the right; F cannot face E, so F takes the last left office, which puts D first on the left with C facing it, A second, and B last on the right. E faces the corridor, looking across to the left side, so his left hand points back towards the entrance. The office there is C's.
Why each option is right or wrong
- (a) A is directly across the corridor from E, in front of him.
- (b) B is on E's right, further down the corridor.
- (c) Correct: C is the right-side office nearest the entrance, on E's left.
- (d) D is on the opposite side of the corridor, facing C.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2018, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.