Number Series Completion - General Inteligence & Reasoning MCQ Questions and Answers

Each term at an even place in the series is the product of its two adjacent terms.
Thus, if the missing term be x, then we have :
7 × x = 56 or x = 56 ÷ 7 = 8

The sum of any three consecutive terms of the series gives the next term,
So, missing number = 8 + 15 + 27 = 50

Let the missing terms of the series be x₁ and x₂.
Thus, the sequence 20, 20, 19, 16, 17, 13, 14, 11. x₁, x₂ is a combination of two series:
I. 20, 19, 17, 14, x₁ and
II. 20, 16, 13, 11, x₂
The pattern in I is - 1, - 2, - 3,..............So, missing term, x₁= 14 - 4 = 10
The pattern in II is - 4, - 3, - 2,.......... So,missing term, x₂ = 11 - 1 = 10

The given sequence is a combination of two series:
I. 45, 47, 49, 51, 53 and
II. 54, ?, 56, 57
Clearly, II. consists of consecutive natural numbers, starting from 54.
so, missing term = 55.

Let the missing terms of the series be x₁ and x₂.
Thus, the sequence 2, 15, 4, 12, 6, 7, x₁, x₂ is a combination of two series:
I. 2, 4, 6, x₁ and
II. 15, 12, 7, x₂
I consists of consecutive even numbers. So, missing term, x₁= 8
The pattern in II is - 3, - 5, ........So, missing term x₂ = 7 - 7 = 0

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

The given sequence is a combination of two series:
I. 0, 3, 8, 15, 24, ? and
II. 2, 5, 10, 17, 26
The pattern in each one of I and II is + 3, + 5, + 7, + 9,..............
So, missing term = 24 + 11 = 35

The given series is a triangular pattern series.
So, we have
3       10       29       66       127       ?
     7       19       37       61
         12        18      24
              6           6
So, missing term
= 127 + (61 + 24 + 6)
= 127 + 91
= 218

The term of the given series are numbers formed by joining together consecutive odd numbers in order i.e., 1 and 3, 3 and 5, 5 and 7, 7 and 9, 9 and 11...................
So, missing term = number formed by joining 11 and 13 = 1113

The sequence in the numerators is + 2, + 3, + 4, + 5 and that in the denominators is + 4, + 6, + 8, + 10
So, the numerator of the missing fraction should be (4 + 3)i.e., 7 and the denominator should be (7 + 6)i.e., 13. Thus, the missing term is ⁷/₁₃ .