Explanation

Firstly we have to find the pattern of the sequence,

In the same way, if we take the missing term as 

3, 8, 6, 17, ?, 20

3 x 2 + 2 = 8 

6 x 2 + 2 = 14

a x 2 + 2 = 20

a x 2 = 18 

a = 18/ 2

a = 9

ND-21-5-2023