Question

In the Number series given below, one number is missing. Series is followed by five alternatives. One of them is the right answer. Identify and indicate it as per the "Instructions".

$1,11,35,79,....$

• A. $81$
• B. $93$
• C. $149$
• D. $124$
• E. $136$

Answer 1

The correct option is C $149$

To get the last term, we must observe the pattern followed in the first four terms:

On careful observation, we find the general term of this series is : $T_n=n^3+n^2-1$

We verify :

$n=1$ :

$T_1=1^3+1^2-1=1$

$n=2$ :

$T_2=2^3+2^2-1=11$

$n=3$ :

$T_3=3^3+3^2-1=35$

$n=4$ :

$T_4=4^3+4^2-1=79$

Similarly, we put:

$n=5$ :

$T_5=5^3+5^2-1=149$

Thus, option C is the correct answer