Find the wrong term in the series: 7, 28, 63, 124, 215, 342, 511

A28 ✓ Correct

B63

C342

D511

Correct answer: (A) 28

Explanation

The wrong term is 28.

Terms follow n^3 - 1 for n = 2, 3, 4, ...

2^3 - 1 = 7, 3^3 - 1 = 26, 4^3 - 1 = 63.

Correct series: 7, 26, 63, 124, 215, 342, 511.

The second term should be 26, so 28 is wrong.

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