Reasoning : Logical Reasoning & Analytical Ability

Q 164 / 325

UPSC CSE Prelims 2018

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 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.

Who is/are Fs immediate neighbour(s)?

EXPLANATION

Correct Option (1)

To determine F's immediate neighbour(s), the office layout must first be established based on the given conditions:

  • E does not have a corner office. Assuming a standard 3x2 office block (three offices on each side), E must occupy the middle office on the right side of the corridor (R2).
  • E and F are on opposite sides but do not face each other. Since E is at R2, F cannot be at L2 (the middle office on the left side). Therefore, F must be in a corner office on the left side (L1 or L3).
  • F's office is further down the corridor than A's, and both are on the same (left) side. This implies F is at L3 (furthest down) and A is at L2 (closer to the entrance). If A were at L1, placing D (who faces C) would become problematic with F at L3.
  • The offices on the left side are therefore: D (L1), A (L2), F (L3).
  • C and D face each other. Since D is at L1, C must be at R1.
  • B and C occupy offices to the right of the corridor. With C at R1 and E at R2, the remaining office on the right side (R3) must be occupied by B.
  • The final arrangement is:
    • Left side: D (L1), A (L2), F (L3)
    • Right side: C (R1), E (R2), B (R3)
  • In this configuration, F (at L3) has A (at L2) as its immediate neighbour on the same side of the corridor.

Incorrect Options:

  • A and D: While A is an immediate neighbour of F, D is located at L1, which is not adjacent to F (L3).

  • C only: C is at R1, on the opposite side of the corridor and not adjacent to F.

  • B and C: B is at R3, which faces F (L3), but "immediate neighbour" typically refers to adjacent offices on the same side. C is at R1 and is not adjacent to F.