Number Series for SBI PO 2017
Directions (1 – 10): In
these questions, a number series is given. Find out the missing number.
1. 6 15 48 171 ? 3645
a) 716
b) 736
c) 746
d) 720
e) None of these
2. 4 11 36 103 ? 939
a) 345
b) 316
c) 375
d) 355
e) None of these
3. 715 524 333 ? 119 68
a) 224
b) 232
c) 242
d) 252
e) None of these
4. 14, 78, 252, 620, ?, 2394
a) 1340
b) 1290
c) 1470
d) 1860
e) None of these
5. 8 18 51 208 1035 ?
a) 6776
b) 6263
c) 6463
d) 6216
e) None of these
6. 12 42 156 606 2400 ?
a) 9186
b) 9470
c) 9570
d) 9486
e) None of these
7. 14 26 62 122 206 ?
a) 310
b) 312
c) 314
d) 313
e) None of these
8. 6 8 16 42 122 ?
a) 364
b) 366
c) 362
d) 361
e) None of these
9. 61 49 57 41 45 ?
a) 58
b) 32
c) 60
d) 25
e) None of these
10. 5 6 14 45 ? 925
a) 150
b) 155
c) 140
d) 184
e) None of these
Solutions:
1. D) (6 * 1) +
(1 * 9) = 15
(15 * 2) + (2 * 9)= 48
(48 * 3) + (3 * 9)= 171
(171 * 4) + (4 * 9) = 720
(720 * 5) + (5 * 9) = 3645
2. B) 4 * 3 – 1 = 11
11 * 3 + 3 = 36
36 * 3 – 5 = 103
103 * 3 + 7 = 316
316 * 3 – 9 = 939
3. A) 9³ – 14 = 715
8³ + 12 = 524
7³ – 10 = 333……
4. B) 2^4 – 2, 3^4 – 3, 4^4 – 4, 5^4 – 5…
5. D) 8 * 2 + 2 = 18
18 * 3 – 3 = 51
51 * 4 + 4 = 208
208 * 5 – 5 = 1035….
6. C) (12 * 4) – 6 = 48 – 6 = 42
(42 * 4) – 12 = 168 – 12 = 156
(156 * 4) – 18 = 624 – 18 = 606
(606 * 4) – 24 = 2424 – 24 = 2400
(2400 * 4) – 54 = 9600 – 30 = 9570
7. C) 14 + (1 * 12) = 14 + 12 = 26
26 + (3 * 12) = 26 + 36 = 62
62 + (5 * 12) = 62 + 60 = 122
122 + (7 * 12) = 122 + 84 = 206
206 + (9 * 12) = 206 + 108 = 314
8. A) 6 + 2 = 8
8 + 8(= 3 * 2 + 2) = 16
16 + 26(= 3 * 8 + 2) = 42
42 + 80(= 3 * 26 + 2) = 122
122 + 242(= 3 * 80 + 2) = 364
9. D)
10. D) (5*1)+1 = 6
(6*2)+2 = 14
(14*3)+3 = 45
(45*4)+4 = 184
