Difficult Number Series Questions and Answers

Directions: The following series are based on a specific pattern. In these series one number is wrong, find that odd one.

5, 12, 23, 50, 141, ?
A) 415
B) 430
C) 439
D) 488
E) 452

View Answer
Option D
Pattern:
5……….12………23………..50……….141…………488
….+7…….+11……….+27……….+91………+347
………+4……..+16……….+64………+256
7, 13, 25, 45, 75, ?
A) 117
B) 153
C) 209
D) 123
E) 141

View Answer
Option A
Pattern:
7 + (2×3) = 13
13 + (3×4) = 25
25 + (4×5) = 45
45 + (5×6) = 75
75 + (6×7) = 117
4, 11, 19, 41, ?, 161
A) 62
B) 108
C) 79
D) 90
E) 85

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Option C
Pattern:
4 × 2 + 3 = 11
11 × 2 – 3 = 19
19 × 2 + 3 = 41
41 × 2 – 3 = 79
79 × 2 + 3 = 161
4, 8, 21, 59, ?, 314
A) 146
B) 134
C) 125
D) 191
E) 126

View Answer
Option A
Pattern:
4……….8………21………..59……….146…………314
….+4…….+13…….+38………+87………+168
………+3²…….+5²……..+7²………+9²
11, 6, 5, 9, 16, ?
A) 66.5
B) 78.5
C) 89.5
D) 42.5
E) 31.5

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Option D
Pattern:
11 ×0.5 + 0.5 = 6
6 ×1 – 1 = 5
5 ×1.5 + 1.5 = 9
9 ×1 – 1 = 16
16 ×2.5 + 2.5 = 42.5
5, 8, 28, 162, ?, 12870
A) 1738
B) 2318
C) 1288
D) 2224
E) 2950

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Option C
Pattern:
×2 – 2, ×4 – 4, ×6 – 6, ×8 – 8, ×10 – 10.
3, 5, 10, 20, 37, ?
A) 68
B) 77
C) 78
D) 61
E) 63

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Option E
Pattern:
+ (1²+1), + (2²+1), + (3²+1), + (4²+1), + (5²+1)
21, 35, 56, 91, 154, ?
A) 273
B) 289
C) 231
D) 240
E) 245

View Answer
Option A
Pattern:
21 × 2 – 7 = 35
35 × 2 – 14 = 56
56 × 2 – 21 = 91
91 × 2 – 28 = 154
154 × 2 – 35 = 273
5, 7, 11, 37, 143, ?
A) 733
B) 721
C) 764
D) 750
E) 784

View Answer
Option B
Pattern:
5 × 1 + 2 = 7
7 × 2 – 3 = 11
11 × 3 + 4 = 37
37 × 4 – 5 = 143
143 × 5 + 6 = 721
5, 7, 25, 131, ?, 8335
A) 865
B) 914
C) 1025
D) 802
E) 925

View Answer
Option E
Pattern:
5 × 1 + 2 = 7
7 × 3 + 4 = 25
25 × 5 + 6 = 131
131 × 7 + 8 = 925
925 × 9 + 10 = 8335

Quantitative Aptitude: Number Series Set 27

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