UPSC Prelims 2026 · CSAT Paper 2 · Set DMathematicsQ 75 / 80

UPSC Prelims 2026 CSAT Paper 2 — Question 75

Question

The top of a table is rectangular and its dimensions are 6' × 10'. Two rectangular portions of the table top are painted in blue colour; both these portions have dimensions 2.5' × 8' and each of them has exactly two sides common with two edges of the table top. If the table is fixed to the ground and the remaining portion of the table top is painted white, how many different patterns are possible when observed from above?

(a)2
(b)4
(c)6
(d)8

UnlockIAS answer: (b)4

Solution

Each 2.5' × 8' strip must corner-anchor with its 8' side along a 10' edge and its 2.5' side along a 6' edge. The two non-overlapping strips can sit both on the left, both on the right, or along either diagonal — 4 distinct patterns, since the fixed table makes mirror images distinguishable.

UnlockIAS expert key, prepared 24 May 2026 and cross-verified by re-deriving the answer — this is our key, not the official UPSC provisional key (awaited).

Section

Mathematics

Topic Reference

Spatial — Painted patterns

Official UPSC key still awaited

UPSC has announced (PIB Release 2262441, 18 May 2026) that the provisional answer key for CSE Prelims 2026 will be released “soon after Exam”. Until then, use the CSAT score calculator for your qualifying-status estimate, and join the per-question discussion below.

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Official Notification

PIB Release 2262441

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