54
Q:

Find out the wrong number in the given sequence of numbers.

1, 2, 6, 15, 31, 56, 91

A) 31 B) 91
C) 56 D) 15

Answer:   B) 91



Explanation:

1, 1 + 12 = 2, 2 + 22 = 6, 6 + 32 = 15, 15 + 42 = 31, 31 + 52 = 56, 56 + 62 = 92

Last number of given series must be 92 not 91.

Subject: Odd Man Out