Number Series Asked in SBI PO Prelims Exam (Slot-I) - 09.07.2016

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

1. 150            102            70            46            26            ?

a) 16

b) 8

c) 10

d) 2

e) 4

2. 10            14            28            52            134            ?

a) 302

b) 268

c) 300

d) 304

e) 208 

3. 4500            900            90            6            ?            0.012

a) 0.3

b) 3

c) 3.33

d) 0.33

e) 3.3 

4. 24            11            10            14            27            ?

a) 66

b) 70.5

c) 68

d) 66.5

e) 68.5 

5. 8            7            12            33            128            ?

a) 528

b) 365

c) 653

d) 825

e) 635

Answers: 

1. b) 8

Solution:

2. d) 304

Solution:

10*3 - 2= 28

14*4 - 4= 52

28*5 - 6= 134

52*6- 8= 304 

3. a) 0.3

Solution:

4500/5 = 900

900/10 = 90

90/15 = 6

6/20 = 0.3

0.3/25 = 0.012 

4. d) 66.5

Solution:

24*(1/2) – 1 = 11

11*(2/2) – 1 = 10

10*(3/2) – 1 = 14

14*(4/2) – 1 = 27

27*(5/2) – 1 = 66.5 

5. e) 635

Solution:

8*1 – 1 = 7

7*2 – 2 = 12

12*3 – 3 = 33

33*4 – 4 = 128

128*5 – 5 = 635 

Thanks.