Number series is one of the most common topics from the Quantitative Aptitude section from which questions are asked in the various Bank exams. A number series is nothing but a sequence of numbers arranged in some logical way. This topic basically consists of a set of numbers connected by a specific pattern and you need to identify the pattern and answer the missing number or you may be asked to identify the number that doesn't fit the pattern.
Directions (Qs. 1 - 25): Find the MISSING term in the given series:
1. 14, 27, 44, 65, ..........., 119.
A) 38 B) 90 C) 97 D) 39 E) None of these
Sol: 1 + 22 + 32 = 14
2 + 32 + 42 = 27
3 + 42 + 52 = 44
4 + 52 + 62 = 65
5 + 62 + 72 = 90
6 + 72 + 82 = 119
Ans: B
2. 180, 190, 205, 225, ?, 280
A) 510 B) 500 C) 350 D) 250 E) None of these
Sol: 180 + 10 = 190
190 + 15 = 205
205 + 20 = 225
225 + 25 = 250
250 + 30 = 280
Ans: D
3. 15, 120, 840, 5040, 25200, ...........
A) 100800 B) 250000 C) 198000 D) 240000 E) None of these
Sol: 15 × 8 = 120
120 × 7 = 840
840 × 6 = 5040
5040 × 5 = 25200
25200 × 4 = 100800
Ans: A
4. 400, 500, 581, 645, 694, .........
A) 801 B) 651 C) 730 D) 900 E) None of these
Sol: 400 + 102 = 500
500 + 92 = 581
581 + 82 = 645
645 + 72 = 694
694 + 62 = 730
Ans: C
5. 51, 57, 67, 81, 99, ..........., 145
A) 100 B) 121 C) 120 D) 125 E) None of these
Sol: 51 + 6 = 57
57 + 10 = 67
67 + 14 = 81
81 + 18 = 99
99 + 22 = 121
121 + 24 = 145
Ans: B
6. 10, 42, 170, 682, .........., 10922
A) 2380 B) 1880 C) 2730 D) 1947 E) None of these
Sol: 10 × 4 + 2 = 42
42 × 4 + 2 = 170
170 × 4 + 2 = 682
682 × 4 + 2 = 2730
2730 × 4 + 2 = 10922
Ans: C
7. 24, .........., 212, 635, 1904, 5711,17132
A) 96 B) 94 C) 52 D) 71 E) None of these
Sol: 24 × 3 − 1 = 71
71 × 3 − 1 = 212
212 × 3 − 1 = 635
635 × 3 − 1 = 1904
1904 × 3 − 1 = 5711
5711 × 3 − 1= 17132
Ans: D
8. 18, ............, 38, 116, 466, 2332
A) 30 B) 40 C) 38 D) 42 E) None of these
Sol: 16 × 1 + 2 = 18
18 × 2 + 2 = 38
38 × 3 + 2 = 116
116 × 4 + 2= 466
466 × 5 + 2 = 2332
Ans: C
9. 32, 67, 137, .............., 557, 1117, 2237
A) 265 B) 271 C) 280 D) 277 E) None of these
Sol: 32 × 2 + 3 = 67
67 × 2 + 3 = 137
137 × 2 + 3 = 277
277 × 2 + 3 = 557
557 × 2 + 3 = 1117
1117 × 2 + 3 = 2237
Ans: D
10. 16, 18, 30, 52, 84, 126, ...........
A) 404 B) 114 C) 340 D) 178 E) None of these
Sol: 16 + 2 = 18
18 + 12 = 30
30 + 22 = 52
52 + 32 = 84
84 + 42 = 126
126 + 52 = 178
Ans: D
11. 11, 29, ............, 137, 281, 569, 1145
A) 40 B) 50 C) 60 D) 65 E) None of these
Sol: 11 × 2 + 7 = 29
29 × 2 + 7 = 65
65 × 2 + 7 = 137
137 × 2 + 7 = 281
281 × 2 + 7 = 569
569 × 2 + 7 = 1145
Ans: D
12. 40, 121, 185, 234, 270, 295, .............
A) 312 B) 321 C) 314 D) 311 E) None of these
Sol: 40 + 92 = 121
121 + 82 = 185
185 + 72 = 234
234 + 62 = 270
270 + 52 = 295
295 + 42 = 311
Ans: D
13. 23, 49, 151, 609, ............, 18313
A) 2424 B) 2462 C) 3514 D) 3051 E) None of these
Sol: 23 × 2 + 3 = 49
49 × 3 + 4 = 151
151 × 4 + 5 = 609
609 × 5 + 6 = 3051
3051 × 6 + 7 = 18313
Ans: D
14. 12, 49.5, ............, 799.5, 3199.5, 12799.5
A) 187.5 B) 197.5 C) 207.5 D) 199.5 E) None of these
Sol: 12 × 4 + 1.5 = 49.5
49.5 × 4 + 1.5 = 199.5
199.5 × 4 + 1.5 = 799.5
799.5 × 4 + 1.5 = 3199.5
3199.5 × 4 + 1.5 = 12799.5
Ans: D
15. 31, 153, 763, 3813, .............
A) 19063 B) 32301 C) 30602 D) 13403 E) None of these
Sol: 31 × 5 − 2 = 153
153 × 5 − 2 = 763
763 × 5 − 2 = 3813
3813 × 5 − 2 = 19063
Ans: A
16. 9, 35, 136, 535, ............., 8471
A) 2092 B) 2124 C) 1992 D) 2292 E) None of these
Sol: 9 × 4 − 1 = 35
35 × 4 − 4 = 136
136 × 4 − 9 = 535
535 × 4 − 16 = 2124
2124 × 4 − 25 = 8471
Ans: B
17. 6, 12, .........., 52, 107, 218, 441
A) 20 B) 42 C) 25 D) 27 E) None of these
Sol: 6 × 2 + 0 = 12
12 × 2 + 1 = 25
25 × 2 + 2 = 52
52 × 2 + 3 = 107
107 × 2 + 4 = 218
218 × 2 + 5 = 441
Ans: C
18. 19, 18, 34, ........., 392, 1955, 11724
A) 99 B) 151 C) 171 D) 72 E) None of these
Sol: 19 × 1 − 1 = 18
18 × 2 − 2 = 34
34 × 3 − 3 = 99
99 × 4 − 4 = 392
392 × 5 − 5 = 1955
1955 × 6 − 6 = 11724
Ans: A
19. 9, 22, 70, 284, ..........
A) 2523 B) 2620 C) 2124 D) 1424 E) None of these
Sol: 5 × 1 + 4 = 9
9 × 2 + 4 = 22
22 × 3 + 4 = 70
70 × 4 + 4 = 284
284 × 5 + 4 = 1424
Ans: D
20. 11, 28, 79, 232, 691, ............, 6199
A) 1875 B) 1795 C) 2815 D) 2068 E) None of these
Sol: 11 × 3 − 5 = 28
28 × 3 − 5 = 79
79 × 3 − 5 = 232
232 × 3 − 5 = 691
691 × 3 − 5 = 2068
2068 × 3 − 5 = 6199
Ans: D
21. 13, 24, 69, 272, 1355, ...........
A) 5644 B) 5624 C) 8124 D) 5544 E) None of these
Sol: 14 × 1 − 1 = 13
13 × 2 − 2 = 24
24 × 3 − 3 = 69
69 × 4 − 4 = 272
272 × 5 − 5 = 1355
1355 × 6 − 6 = 8124
Ans: C
22. 12, 24 , .........., 144, 432, 864 , 2592
A) 64 B) 68 C) 70 D) 72 E) None of these
Sol: 12 × 2 = 24
24 × 3 = 72
72 × 2 = 144
144 × 3 = 432
432 × 2 = 864
864 × 3 = 2592
Ans: D
23. 39, 78, 195, 585, ..........., 8190
A) 1060.5 B) 2047.5 C) 1360 D) 1560 E) None of these
Sol: 26 × 1.5 = 39
39 × 2 = 78
78 × 2.5 = 195
195 × 3 = 585
585 × 3.5 = 2047.5
2047.5 × 4 = 8190
Ans: B
24. 14.5, 16.5, 20.5, 28.5, 44.5, 76.5, .............
A) 140.5 B) 150.5 C) 161.6 D) 171.6 E) None of these
Sol: 14.5 + 2 = 16.5
16.5 + 4 = 20.5
20.5 + 8 = 28.5
28.5 + 16 = 44.5
44.5 + 32 = 76.5
76.5 + 64 = 140.5
Ans: A
25. 8, 19, 44, 97, ..........., 427, 872
A) 280 B) 206 C) 270 D) 288 E) None of these
Sol: 8 × 2 + 3 = 19
19 × 2 + 6 = 44
44 × 2 + 9 = 97
97 × 2 + 12 = 206
206 × 2 + 15 = 427
427 × 2 + 18 = 872
Ans: B