Find the wrong number in the following sequence: 125, 127, 130, 135, 142, 153, 165

A130

B142

C153

D165 ✓ Correct

Correct answer: (D) 165

Explanation

The wrong number is 165.

The differences should be consecutive primes 2, 3, 5, 7, 11, 13.

125 + 2 = 127, + 3 = 130, + 5 = 135, + 7 = 142.

142 + 11 = 153, and 153 + 13 = 166.

The listed 165 breaks this, since it should be 166.

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