Number Series Asked in IBPS PO - VI (Prelim) Exam - 22.10.2016 (3rd Shift)

Directions (1-5): What should come in place of the question mark (?) in the following number series?

#1.

12, 6.5, 7.5, 17, 72, ?
a) 356
b) 82
c) 185
d) 292
e) 584

#2.

463, 220, 139, 112, ?, 100
a) 101
b) 100
c) 104
d) 103
e) 102

#3.

17, 30, 21, 34, 25, ?
a) 38
b) 30
c) 27
d) 36
e) 40

#4.

31, 33, 40, 68, 131, ?
a) 232
b) 257
c) 132
d) 250
e) 275

#5.

11, 16, 34, 66, 113, ?
a) 130
b) 160
c) 176
d) 175
e) 177

Answers:

1. e) 584
Solution:
12 x 0.5 + 0.5 = 6.5
6.5 x 1 + 1 = 7.5
7.5 x 2 + 2 = 17
17 x 4 + 4 = 72
72 x 8 + 8 = 584

2. d) 103
Solution:
463 – 220 = 243
220 – 139 = 81
139 – 112 = 27
112 – ? = 9
? – 100 = 3
So, ? = 112 – 9 = 103

3. a) 38
Solution:
17 +13 = 30
30 – 9 = 21
21 +13 = 34
34 – 9 = 25
25 + 13 = 38

4. b) 257
Solution:
31 + (1³ + 1) = 31 + 2 = 33
33 + (2³ - 1) = 33 + 7 = 40
40 + (3³ + 1) = 40 + 28 = 68
68 + (4³ - 1) = 68 + 63 = 131
131 + (5³ + 1) = 131 + 126 = 257

5. c) 176
Solution:

Thanks.