Question

In following questions, one term in number series is incorrect.
Find out the incorrect number 1, 5, 9, 16, 25, 37, 49

• A. 9
• B. 15
• C. 25
• D. 37

Answer 1

The correct option is B 15

The given sequence is a combination of two series :
I. 1, 9, 25, 49 and
II. 5, 15, 37
The pattern in I is + 8, + 16, + 24.
The sequence in II is $2^2+1,4^2+1,6^2+1.$
So, 16 is wrong and must be replaced by $(4^2+1)$ i.e. 17.