Multiple choice

Find out the wrong number in the number series given below. $1 \quad 2 \quad 6 \quad 15 \quad 31 \quad 56 \quad 91$

  1. 31

  2. 91

  3. 56

  4. 15

  5. 2
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The series follows the pattern of differences of consecutive squares: 1²-0=1, 2²-2=6, 3²-6=3 (not 15), 4²-3=13 (not 31), 5²-13=12 (not 56), 6²-12=24 (not 91). The correct pattern should be: 1, 6, 3, 13, 12, 24... where each term is n² minus the previous term. Option B (91) is identified as the wrong number in the given sequence.

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