Find out the wrong number in the given sequence of numbers 1, 2, 6, 15, 31, 56, 91
Answer: B
1, 1 + 1⊃2; = 2, 2 + 2⊃2; = 6, 6 + 3⊃2; = 15, 15 + 4⊃2; = 31, 31 + 5⊃2; = 56, 56 + 6⊃2; = 92
Last number of given series must be 92 not 91.