I could not find the series pattern.. but I observed here every even number is followed by a odd number... so 50 should have been followed by a odd number but 64 is a even!!... so I chose option (C).. anyway your solution is perfect!!

Dark Mode

2,036 views

16 votes

Best answer

If $\large a_1,a_2,a_3\ldots a{_n}$ is the series and $i = 1$ to $n,$ then the series is defined as $a_i=i{^2} + 1.$

i.e the $i^{\text{th}}$ term is $1$ plus the square of $i.$

Series will be as follows $:1^{2} +1 ,2^{2}+ 1,3^{2} +1,4^{2}+1\ldots n^{2} + 1$

$\qquad\qquad\qquad\qquad\quad\;\; 2,5,10,17,26,37,50,65$

Hence $64$ does not belong to the series.

Correct Answer: $C$

i.e the $i^{\text{th}}$ term is $1$ plus the square of $i.$

Series will be as follows $:1^{2} +1 ,2^{2}+ 1,3^{2} +1,4^{2}+1\ldots n^{2} + 1$

$\qquad\qquad\qquad\qquad\quad\;\; 2,5,10,17,26,37,50,65$

Hence $64$ does not belong to the series.

Correct Answer: $C$

0