Odd Man Out Questions

The given series is 12, 48, 168, 502, 1260

12

12 x 4 = 48

48 x 3.5 = 168

168 x 3 = 504

504 x 2.5 = 1260

Hence, the odd man out in the given series is 502.

Here the given series follows a pattern that, multiplying the number with odd numbers in decreasing order starting with 13. That is,

6 × 13 = 78

65 × 11 = 858

858 × 9 = 7722

7722 × 7 = 54054

54054 × 5 = 270270

Hence, the wrong number is 54055

1 x 1 + 1 x 1 = (1 + 1) = 2

2 x 2 + 2 x 2 = (4 + 4) = 8

8 x 3 + 3 x 3 = (24 + 9) = 33

33 x 4 + 4 x 4 = (132 + 16) = 148

148 x 5 + 5 x 5 = (740 + 25) = 765.

Given Number series is 18     37     76     155     314     635

follows a pattern that, 

18

18 x 2 +1 = 37

37 x 2 +2 = 76

76 x 2 +3 = 155

155 x 2 +4 = 314

314 x 2 +5 = 633 not 635

Hence, the odd man is 635.

There should be 90 instead of 80
so we can have a series
5, 5x3, 15x2, 30x3, 90x2, 180x3, 540x2 and 1080x3 and so on...