Practice MCQ Questions and Answer on Number Series Completion
121.
Find the missing term: 1, 5, 13, 25, 41, ?
(A) 51
(B) 57
(C) 61
(D) 63
Solution:
The pattern is + 4, + 8, + 12, + 16,.......... So, missing term = 41 + 20 = 61
122.
3, 4, 7, 8, 11, 12, ... What number should come next?
(A) 7
(B) 10
(C) 14
(D) 15
Solution:
This alternating addition series begins with 3; then 1 is added to give 4; then 3 is added to give 7; then 1 is added, and so on.
123.
4, 7, 26, 10, 13, 20, 16, ... choose which pair of numbers comes next?
(A) 14, 4
(B) 14, 17
(C) 18, 14
(D) 19, 13
Solution:
Answer & Solution Answer: Option E Solution: Two patterns alternate here, with every third number following the alternate pattern. In the main series(1st series) 4, 7, 10,13, 16 ..... beginning with 4, 3 is added to each number to arrive at the next. Secondary series (2nd series): 26, 20, ... beginning with 26, 6 is subtracted from each number to arrive at the next. Therefore Next two number is 19(from 1st series), 14(from 2nd series). 19,14
124.
Find the missing term: 48, 24, 96, 48, 192, ?
(A) 76
(B) 90
(C) 96
(D) 98
Solution:
The pattern is ÷ 2, × 4, ÷ 2, × 4,........... So, missing term = 192 ÷ 2 = 96
125.
Find out the wrong term: 325, 259, 202, 160, 127, 105, 94
(A) 94
(B) 127
(C) 202
(D) 259
Solution:
The correct pattern is - 66, - 55, - 44, - 33, - 22, - 11.So, 202 is wrong and must be replaced by (259 - 55) i.e., 204.
126.
Find out the wrong term: 0, 2, 3, 5, 8, 10, 15, 18, 24, 26, 35
(A) 18
(B) 24
(C) 26
(D) 10
Solution:
The given sequence is a combination of two series:I. 0, 3, 8, 15, 24, 35 and II. 2, 5, 10, 18, 26The pattern in both I and II is + 3, + 5, + 7, + 9, .........So, in II. 18 is wrong and must be replaced by (10 + 7) i.e., 17.
127.
Find the missing term : 4, 6, 10, 16, 24, ?
(A) 40
(B) 34
(C) 30
(D) 28
Solution:
1st term : 4 2nd term : 4 + 2 = 6 3rd term : 6 + 4 = 10 4th term : 10 + 6 = 16 5th term : 16 + 8 = 24 So, 6th term : 24 + 10 = 34
128.
58, 52, 46, 40, 34, ... What number should come next?
(A) 26
(B) 28
(C) 30
(D) 32
Solution:
This is a simple subtraction series. Each number is 6 less than the previous number.
129.
Find out the wrong term: 2, 3, 4, 4, 6, 8, 9, 12, 16
(A) 3
(B) 6
(C) 9
(D) 12
Solution:
The given sequence is a combination of three series:I: 1st, 4th, 7th terms i.e., 2, 4, 9.....II: 2nd, 5th, 8th terms i.e.,3, 6, 12.......III: 3rd, 6th, 9th terms i.e., 4, 8, 16..................In each one of I, II and III, each term is twice the preceding term.So, 9 is wrong and must be replaced by (4 × 2) i.e., 8.
130.
Find the missing term: 1, 1, 2, 6, 24, ?, 720
(A) 100
(B) 104
(C) 108
(D) 120
Solution:
The pattern is × 1, × 2, × 3, × 4, .............So, missing term = 24 × 5 = 120