Number Series Asked in SBI PO Prelims Exam (Slot-I) - 02.07.2016

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

1. 7        5        7        17        63       ?

a) 308

b) 302

c) 309

d) 409

e) 390

2. 50      ?     61      89      154       280

a) 52

b) 51

c) 60

d) 62

e) 60 

3. 17     19       25      37      ?       87

a) 47

b) 37

c) 57

d) 67

e) 75

4. 11      14      19       28      43       ?

a) 55

b) 44

c) 77

d) 88

e) 66 

5. 26     144       590      1164      ?

a) 1296

b) 1182

c) 2059

d) 1182

e) 1181

Answers:

1. c) 309

Solution:
7 x 1 – 2 = 5
5 x 2 – 3 = 7
7 x 3 – 4 = 17
17 x 4 – 5 = 63
63 x 5 – 6 = 309 

2. a) 52

Solution:
50..50+(1^3+1) = 52
52+(2^3+1)=61.
61+(3^3+1)=89
89+(4^3+1)=154
154 + (5^3+1) = 280 

3. c) 57

Solution:
17 + 1 x 2 = 19
19 + 2 x 3 = 25
25 + 3 x 4 = 37
37 + 4 x 5 = 57
57 + 5 x 6 = 87 

4. e) 66

Solution:
3….5...9...15...23
…2....4....6....8…

Answer 43+23= 66 

5. b) 1182

Solution:
26 x 6 – 12 = 144
144 x 4 + 14 = 590
590 x 2 – 16 = 1164
1164 x 1 + 18 = 1182 

Thanks.