UPSC Prelims 2026 · CSAT Paper 2 · Set DMathematicsQ 37 / 80

UPSC Prelims 2026 CSAT Paper 2 — Question 37

Question

In a sequence of numbers, each number other than the first two is the sum of the two immediately preceding numbers from it. If the first two numbers in the sequence are 4 and 7, then the sixth number is

(a)29
(b)37
(c)43
(d)47

UnlockIAS answer: (d)47

Solution

The sequence is 4, 7, 11, 18, 29, 47. The sixth term is 47.

UnlockIAS expert key, prepared 24 May 2026 and cross-verified by re-deriving the answer — this is our key. The official UPSC provisional key has been released.

Section

Mathematics

Topic Reference

Numeracy — Number series

Official UPSC Provisional Key Released

The official provisional answer key for CSE Prelims 2026 has been released. Compare your answers with the official key using our CSAT score calculator, and file objections via the QPRep portal before 6:00 PM on 31 May 2026.

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Official Notification

PIB Release 2262441

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