Question

Find the odd one out among the given options.

• A. $120$
• B. $168$
• C. $290$
• D. $380$
• E. $728$

Answer 1

The correct option is D $380$

$120=121-1={11}^2-1$

$168=169-1={13}^2-1$

$290=289+1={17}^2+1$

$728=729-1={27}^2-1$

All numbers are either one more or less than of square of certain number but $380$ is neither one more nor on less than of square of a number.

Hence, D is the correct option.