Practice MCQ Questions and Answer on Number Series Completion
11.
Find the missing term 6, 13, 28, 59, ?
(A) 111
(B) 113
(C) 114
(D) 122
Solution:
The pattern is x2+1 ,x2+2, x2+3,........So, missing term=59x2+4=122
12.
In a given series one term is wrong or missing term: 1, 2, 5, 10, 17, 28
(A) 30
(B) 28
(C) 27
(D) 17
Solution:
The correct sequence is + 1, + 3, + 5, + 7, + 9.So, 28 is wrong and must be replaced by (17 + 9) i.e., 26.
13.
In a given series one term is wrong or missing term: 2, 3, 5, 8, 13, 34
(A) 21
(B) 25
(C) 29
(D) 34
Solution:
Clearly, each term of the series is the sum of the preceding two terms.Now, 8 + 13 = 21 and 13 + 21 = 34.So, the term 21 is missing.
14.
Find the missing term: 28, 33, 31, 36, ?, 39
(A) 32
(B) 34
(C) 38
(D) 40
Solution:
The pattern is + 5, - 2, + 5, - 2,........ So, missing term = 36 - 2 = 34
15.
V, VIII, XI, XIV, __, XX. What number should fill the blank?
(A) IX
(B) XXIII
(C) XV
(D) XVII
Solution:
This is a simple addition series; each number is 3 more than the previous number.
16.
What will come at the place of question mark ? 2/3 , 4/7 , ? , 11/21 , 16/31
(A) 5/9
(B) 6/11
(C) 7/13
(D) 9/17
Solution:
The sequence in the numerators is + 2, + 3, + 4, + 5 and that in the denominators is + 4, + 6, + 8, + 10So, 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 .
17.
What will come at the place of question mark ? 3, 2, 7, 6, 11, ?
(A) 8
(B) 10
(C) 4
(D) 2
Solution:
2nd number is less by 1 than the 1st number and 3rd number is more by 5 than the 2nd number. The same rule follows in other numbers of the series.
18.
Find the missing term: 11, 13, 17, 19, 23, 25, ?
(A) 26
(B) 27
(C) 29
(D) 37
Solution:
The pattern is +2,+4,+2,+4, So, missing term = 25 + 4 = 29
19.
Which of the following will not be a number of the series 1, 8, 27, 64, 125, ....?
(A) 256
(B) 512
(C) 729
(D) 1000
Solution:
The given series consists of cubes of natural numbers only. 256 is not the cube of any natural number.
20.
664, 332, 340, 170, ____, 89. What number should fill the blank?
(A) 85
(B) 97
(C) 109
(D) 178
Solution:
This is an alternating division and addition series: First, divide by 2, and then add 8.