# IBM Number series questions for practice

IBM Number series questions for practice
Find the odd man out.

1. 3, 5, 11, 14, 17, 21

A. 21
B. 17
C. 14
D. 3
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Explanation:

Each of the numbers except 14 is an odd number. The number ’14’ is the only EVEN number.

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2.     8, 27, 64, 100, 125, 216, 343

A. 27
B. 100
C. 125
D. 343
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Explanation:

The pattern is 23, 33, 43, 53, 63, 73. But, 100 is not a perfect cube.

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3.     10, 25, 45, 54, 60, 75, 80

A. 10
B. 45
C. 54
D. 75
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Explanation:

Each of the numbers except 54 is multiple of 5.

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4.     396, 462, 572, 427, 671, 264

A. 396
B. 427
C. 671
D. 264
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Explanation:

In each number except 427, the middle digit is the sum of other two.

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5.     6, 9, 15, 21, 24, 28, 30

A. 28
B. 21
C. 24
D. 30
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Explanation:

Each of the numbers except 28, is a multiple of 3.Find the odd man out.

6.     1, 4, 9, 16, 23, 25, 36

A. 9
B. 23
C. 25
D. 36
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Explanation:

Each of the numbers except 23, is perfect square.

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7.     1, 4, 9, 16, 20, 36, 49

A. 1
B. 9
C. 20
D. 49
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Explanation:

The pattern is 12, 22, 32, 42, 52, 62, 72. But, instead of 52, it is 20 which to be turned out.

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8.     2, 5, 10, 17, 26, 37, 50, 64

A. 50
B. 26
C. 37
D. 64
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Explanation:

(1*1)+1 , (2*2)+1 , (3*3)+1 , (4*4)+1 , (5*5)+1 , (6*6)+1 , (7*7)+1 , (8*8)+1

But, 64 is out of pattern.

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9. 10, 14, 16, 18, 21, 24, 26

A. 26
B. 24
C. 21
D. 18
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Explanation:

Each of the numbers except 21 is an even number.

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10.     16, 25, 36, 72, 144, 196, 225

A. 36
B. 72
C. 196
D. 225
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Explanation:

Each of the numbers except 72 is a perfect square.

Find the odd man out.

11.     331, 482, 551, 263, 383, 362, 284

A. 263
B. 383
C. 331
D. 551
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Explanation:

In each number except 383, the product of first and third digits is the middle one.

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12.     835, 734, 642, 751, 853, 981, 532

A. 751
B. 853
C. 981
D. 532
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Explanation:

In each number except 751, the difference of third and first digit is the middle one.

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13.     41, 43, 47, 53, 61, 71, 73, 81

A. 61
B. 71
C. 73
D. 81
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Explanation:

Each of the numbers except 81 is a prime number.

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14.     3, 5, 7, 12, 17, 19

A. 19
B. 17
C. 5
D. 12
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