Series Completion - General Inteligence & Reasoning MCQ Questions and Answers

The given sequence is a combination of two series :
I. 3, 7, 13, 21, 31, ? and II. 4, 7, 13, 22, 34
The pattern in I is + 4, + 6, + 8, + 10,.....
The pattern in II is + 3, + 6, + 9, + 12,.....
So, missing term = 31 + 12 = 43.

The pattern is - 4, - 9, - 16,.....i.e. - 2², - 3², - 4²,.....
So, missing pattern = 169 - 5² = 169 - 25 = 144.

Clearly, the given series consists of prime numbers starting from 2. So, the missing
term is the prime number after 11, which is 13.

The pattern is + 6, + 9, + 12, + 15, .....
So, missing term = 21 + 12 = 33.

Clearly, 5 x 2 = 10, 10 x 2 = 20, 20 x 2 = 40,.....
So, the series is a G.P. in which a = 5 and r = 2.
Let 1280 be the rath term of the series.
Then, 5x2^n-1 = 1280 ⇔ 2^n-1 = 256 = 2⁸ ⇔ n - 1 = 8 ⇔ n = 9.

The pattern is + 3, + 4, + 5, + 6,.....
So, missing term = 9 + 5 = 14.

The pattern is + 1, x 1, + 2, x 2, + 3, x 3, + 4, x 4, + 5.
So, missing term = 13 x 3 = 39.

The pattern is x 3, + 4, x 5, + 6, x 7,.....
So, missing term = 1127 + 8 = 1135.

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.

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