Question

Select the odd one from the given series:

$3,7,9,21,27,66,81,189,243$

• A. $27$
• B. $66$
• C. $243$
• D. $21$

Answer 1

The correct option is B $66$

Given series is: $3,7,9,21,27,66,81,189,243$
There are two alternate series :

Series I : $3,9,27,81,243$

Series II : $7,21,66,189$

In series I, each number is multiplied by $3$ to get the next number whereas in series II except $66$, all other numbers are obtained by multiplying previous number by $3$.

Also, $63$ should replace $66$.

Hence, option (B) is the correct.