Find the wrong number in the series: 6, 18, 90, 630, 6930, 83160.

A83160 ✓ Correct

B6930

C90

D630

Correct answer: (A) 83160

Explanation

The wrong number is 83160.

Each term multiplies by consecutive primes 3, 5, 7, 11, 13.

6 x 3 = 18, 18 x 5 = 90, 90 x 7 = 630.

630 x 11 = 6930, then 6930 x 13 = 90090.

90090 is expected, so 83160 breaks the pattern.

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