IAS 2018 — CSAT Reasoning

2018mcqmedium

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.
If E sits in his office and faces the corridor, whose office is to his left?

Official previous-year question

Verified 2 Aug 2026.

Options

Did you get this right?

Solution

Correct Option (C)

To determine the office layout, we systematically apply the given conditions:

Officers B and C are on the right side of the corridor, while A is on the left.
The offices of C and D face each other. Since C is on the right, D must be on the left, directly opposite C.
E does not occupy a corner office. Given that there are six officers and three offices on each side, E must be in the middle office on one side.
E and F occupy offices on opposite sides but do not face each other. This implies that if E is in the middle office, F cannot be in the middle office on the opposite side.
F’s office is further down the corridor than A’s, and both are on the same side (left). This confirms A and F are on the left side, with A preceding F.

Based on these deductions:

E must be in the middle office on the right side (let's denote it as R2, where R1 is near the entrance and R3 is at the far end).
Since E (R2) and F are on opposite sides but do not face each other, F must be on the left side (L1 or L3), not L2.
As A and F are on the left side, and A is before F, the arrangement on the left must be A then F. Given F is a corner office (L1 or L3), F must be L3, and A must be L2.
With E at R2, and A at L2, F at L3, the remaining officer on the left is D. D must be L1.
Since D (L1) faces C, C must be R1.
The remaining officer on the right side is B, who must occupy R3.

The final office arrangement is:

Left Side (from entrance to far end): D (L1), A (L2), F (L3)
Right Side (from entrance to far end): C (R1), E (R2), B (R3)

All conditions are satisfied by this arrangement.

If E sits in his office (R2) and faces the corridor (i.e., looks towards the left side offices), his left hand points towards the entrance of the corridor. The office located at R1 (to E's left) is occupied by C.

Incorrect Options:

A: Officer A is in office L2, which is on the opposite side of the corridor, directly in front of E's right-hand view, not to E's immediate left.
B: Officer B is in office R3, which is further down the corridor on E's right side, not to E's immediate left.
D: Officer D is in office L1, which is on the opposite side of the corridor, directly in front of E's left-hand view, not to E's immediate left.

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Correct Option (C)

To determine the office layout, we systematically apply the given conditions:

Officers B and C are on the right side of the corridor, while A is on the left.
The offices of C and D face each other. Since C is on the right, D must be on the left, directly opposite C.
E does not occupy a corner office. Given that there are six officers and three offices on each side, E must be in the middle office on one side.
E and F occupy offices on opposite sides but do not face each other. This implies that if E is in the middle office, F cannot be in the middle office on the opposite side.
F’s office is further down the corridor than A’s, and both are on the same side (left). This confirms A and F are on the left side, with A preceding F.

Based on these deductions:

E must be in the middle office on the right side (let's denote it as R2, where R1 is near the entrance and R3 is at the far end).
Since E (R2) and F are on opposite sides but do not face each other, F must be on the left side (L1 or L3), not L2.
As A and F are on the left side, and A is before F, the arrangement on the left must be A then F. Given F is a corner office (L1 or L3), F must be L3, and A must be L2.
With E at R2, and A at L2, F at L3, the remaining officer on the left is D. D must be L1.
Since D (L1) faces C, C must be R1.
The remaining officer on the right side is B, who must occupy R3.

The final office arrangement is:

Left Side (from entrance to far end): D (L1), A (L2), F (L3)
Right Side (from entrance to far end): C (R1), E (R2), B (R3)

All conditions are satisfied by this arrangement.

Incorrect Options:

A: Officer A is in office L2, which is on the opposite side of the corridor, directly in front of E's right-hand view, not to E's immediate left.
B: Officer B is in office R3, which is further down the corridor on E's right side, not to E's immediate left.
D: Officer D is in office L1, which is on the opposite side of the corridor, directly in front of E's left-hand view, not to E's immediate left.

IAS 2018 — CSAT Reasoning

Options

Did you get this right?

Solution

Correct Option (C)

Incorrect Options:

Your note

IAS Reasoning in other years

More IAS Reasoning questions

Other CSAT topics for IAS

Comprehension

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IAS 2018 — CSAT Reasoning

Options

Did you get this right?

Solution

Correct Option (C)

Incorrect Options:

Your note

IAS Reasoning in other years

More IAS Reasoning questions

Other CSAT topics for IAS

Comprehension

Maths

Keep practicing Reasoning