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

.

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.

.

3. 10, 25, 45, 54, 60, 75, 80

A. 10

B. 45

C. 54

D. 75

.

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.

.

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.

.

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.

.

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.