Odd Man Out Questions

In given Series, all the numbers except 54 are multiples of 5.

With close observation, you will note that each number in the list is in the middle of two prime numbers. Thus:

4 is in the middle of 3 and 5, 6 is in the middle of 5 and 7, 12 is in the middle of 11 and 13, 18 is in the middle of 17 and 19, 30 is in the middle of 29 and 31. 42 is in the middle of 41 and 43, 60 is in the middle of 59 and 61.

Therefore, the next number would be the one that is in the middle of the next two prime numbers, which is 72 (which is in the middle of 71 and 73).

The Given number series 3, 6.5, 14, 29, 64, 136 follows a pattern that

3

3 x 2 + 0.5 = 6.5

6.5 x 2 + 1 = 14

14 x 2 + 2 = 30 ≠29

30 x 2 + 4 = 64

64 x 2 + 8 = 136

Thus the wrong number in the series is 29

The series follows the following pattern

5 X 5 – 5 = 20

20 X 4 – 4 = 76

76 X 3 – 3 = 225

225 X 2 – 2 = 448

Hence, the term 225 denoted by (d) completes the series

From the beginning, the next term comes by adding prime numbers in a sequence of 2, 3, 5, 7, 9, 11, 13... to its previous term. But 165 will not be in the series as it must be replaced by 166 since 153+13 = 166.

All except Parrot are birds of prey.

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

Given number series follows a pattern that,

2

2 x 1.5 + 1 = 4

4 x 1.5 + 1 = 7 (not equal to 8)

7 x 1.5 + 1 = 11.5

11.5 x 1.5 + 1 = 18.25

18.25 x 1.5 + 1 = 28.375

Hence, the odd number in the given number series is 8.