Which number will come next in the given number series? 1, 3, 7, 15, 31, ____

2026

Which number will come next in the given number series?

1, 3, 7, 15, 31, ____

  1. A.

    92

  2. B.

    115

  3. C.

    63

  4. D.

    131

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Show answer & explanation

Correct answer: C

Answer: 63

Justification:

  • Pattern: each term = previous × 2 + 1 (equivalently, add 2, 4, 8, 16, ...).

  • Calculations: 1 × 2 + 1 = 3; 3 × 2 + 1 = 7; 7 × 2 + 1 = 15; 15 × 2 + 1 = 31.

  • Next term: 31 × 2 + 1 = 63.

Missing number = 63.

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