Practice MCQ Questions and Answer on Number Series Completion
51.
28, 25, 5, 21, 18, 5, 14, ... choose which pair of numbers comes next?
(A) 11, 5
(B) 10, 7
(C) 11, 8
(D) 5, 10
Solution:
This is an alternating subtraction series with the interpolation of a random number, 5, as every third number. In the subtraction series, 3 is subtracted, then 4, then 3, and so on.
52.
Find the missing term: 4832, 5840, 6848, ?
(A) 7815
(B) 7846
(C) 7856
(D) 7887
Solution:
The pattern is + 1008. So, the missing term = 6848 + 1008 = 7856.
53.
13, 29, 15, 26, 17, 23, 19, ... choose which pair of numbers comes next?
(A) 21, 23
(B) 20, 21
(C) 20, 17
(D) 25, 27
Solution:
Here, there are two alternating patterns, with every other number following a different pattern. The first pattern begins with 13 and adds 2 to each number to arrive at the next; the alternating pattern begins with 29 and subtracts 3 each time.
The given series is a triangular pattern series.So, we have Series I : 2 9 28 ? 126 217 344 Series II : 7 19 ? ? 91 127 Series III : 12 ? ? ? 36 Clearly, to form a pattern, the missing terms in Series III must be 18, 24, 30So, missing term = 127 + (61 + 24 + 6)= 127 + 91= 218
55.
11, 14, 14, 17, 17, 20, 20, ... choose which pair of numbers comes next?
(A) 23, 23
(B) 23, 26
(C) 21, 24
(D) 24, 24
Solution:
This is a simple addition series with repetition. It adds 3 to each number to arrive at the next, which is repeated before 3 is added again.
56.
Find out the wrong term: 5, 10, 40, 80, 320, 550, 2560
(A) 80
(B) 320
(C) 550
(D) 2560
Solution:
The correct pattern is ×2, ×4, ×2, ×4 . . . . . . So, 550 is wrong and must be replaced by (320 × 2) i.e., 640
57.
What will come at the place of question mark ? 8, 22, 64, 190, 568, ?
(A) 1702
(B) 7767
(C) 6992
(D) 6913
Solution:
Logic: Previous Term * 3 - 2 = Next term. First Term = 8 Second term = 8 * 3 - 2 = 24 - 2 = 22 Third term = 22 * 3 - 2 = 64 Fourth term = 64 * 3 - 2 = 190 Fifth Term = 190 * 3 - 2 = 568 Sixth Term = 568 * 3 - 2 = 1704 - 2 = 1702
58.
Find the missing term: 3, 7, 23, 95, ?
(A) 62
(B) 128
(C) 479
(D) 575
Solution:
The pattern is × 2+1, × 3+2, × 4+3....... So, missing term= 95 × 5 + 4 = 479
59.
Find the missing term: 589654237, 89654237, 8965423, 965423, ?
(A) 58965
(B) 65423
(C) 89654
(D) 96542
Solution:
The digits are removed one by one from the beginning and the end in order alternately so as to obtain the subsequent terms of the series.
60.
6, 20, 8, 14, 10, 8, 12, ... choose which pair of numbers comes next?
(A) 14, 10
(B) 2, 18
(C) 4, 12
(D) 2, 14
Solution:
This is an alternating addition and subtraction series. In the first pattern, 2 is added to each number to arrive at the next; in the alternate pattern, 6 is subtracted from each number to arrive at the next.