Question

Find the term to replace the question mark in order to complete the series.

$5,9,21,37,81,?$

• A. $153$
• B. $150$
• C. $158$
• D. $151$

Answer 1

The correct option is A $153$

The sequence is $\times 2-1,\times 2+3,\times 2-5,\times 2+7,\times 2-9etc$.
The next number is $81\times 2-9=153$.

option A.