Multiple choice

Find the wrong number among the given series 21, 24, 30, 41, 66

  1. 21

  2. 24

  3. 30

  4. 41
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D Correct answer
Explanation

The differences between consecutive terms should double each time: 24-21=3, 30-24=6, [42-30=12], [66-42=24]. The number 41 breaks this pattern because 41-30=11 instead of the expected 12. If 42 were in place of 41, the pattern of doubling differences (3, 6, 12, 24) would hold.

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