2, 5, 9, ?, 20, 27

Answer: Option A

Explanation:

The pattern is + 3, + 4, + 5, + 6,.....

So, missing term = 9 + 5 = 14.

2, 3, 3, 5, 10, 13, ?, 43, 172, 177

Answer: Option C

The pattern is + 1, x 1, + 2, x 2, + 3, x 3, + 4, x 4, + 5.

So, missing term = 13 x 3 = 39.

9, 27, 31, 155, 161, 1127, ?

Answer: Option B

The pattern is x 3, + 4, x 5, + 6, x 7,.....

So, missing term = 1127 + 8 = 1135.

2, 1, 2, 4, 4, 5, 6, 7, 8, 8, 10, 11, ?

The given sequence is a combination of three series :

I. 1st, 4th, 7th, 10th, 13th terms i.e. 2, 4, 6, 8, ?

II. 2nd, 5th, 8th, 11th terms i.e. 1, 4, 7, 10

III. 3rd, 6th, 9th, 12th terms i.e. 2, 5, 8, 11

Clearly, I consists of consecutive even numbers. So, the missing term is 10.

Which of the following will not be a number of the series 1, 8, 27, 64, 125,.....?

The given series consists of cubes of natural numbers only. 256 is not the cube of

any natural number.