Question

Find the wrong term of the series :

$3,7,9,28,27,84,81,448,243$

• A. $84$
• B. $81$
• C. $28$
• D. $7$

Answer 1

The correct option is A $84$

The given series $3, 7, 9, 28, 27, 84, 81 ,448, 243$ consists of two series.
I: $(3,9,27,81,243)$

II: $(7,28,84,448)$
In I, each of the next term is thrice of the previous term.
In II, each of the next term is four times of previous term.
Clearly, $28\times 4=112\times 4=448$.

So, $84$ is the wrong term in the given sequence.
Hence, option A.