# IBM Number series questions for practice

I**BM 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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Answer: Option C

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

.

Answer: Option B

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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Answer: Option C

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

.

Answer: Option B

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

.

Answer: Option A

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

.

Answer: Option B

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

.

Answer: Option C

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

.

Answer: Option D

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.

.

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

A. 26

B. 24

C. 21

D. 18

.

Answer: Option C

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

.

Answer: Option B

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

.

Answer: Option B

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

.

Answer: Option A

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

.

Answer: Option D

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

.

Answer: Option D

Explanation:

Each of the numbers is a prime number except 12.