A. 21

B. 17

C. 12

D. 3

Answer:C. 12

Explanation: Each of the numbers except 12 is an odd number. The number '12' is the only EVEN number. So the answer is 12.

A. 27

B. 100

C. 125

D. 216

Answer:B. 100

Explanation: The pattern is 13 23, 33, 43, 53, 63. But, 100 is not a perfect cube.

A. 10

B. 45

C. 58

D. 60

Answer:C. 58

Explanation: Each of the numbers except 58 is multiple of 5.

A. 26

B. 21

C. 24

D. 30

Answer:A. 26

Explanation: Each of the numbers except 26, is a multiple of 3.

A. 23

B. 92

C. 100

D. 112

Answer:B. 92

Explanation: 1, 1 + 12 = 2, 2 + 22 = 6, 6 + 32 = 15, 15 + 42 = 31, 31 + 52 = 56, 56 + 62 = 92 Last number of given series must be 92 not 91.

Exercise 1