Directions (1-15): In the following number series, a wrong number is given. Find out that wrong number.

1. 2,  11,  38,  197,  1172,  8227,  65806
(1) 11
(2) 38
(3) 197
(4) 1172
(5) 8227

2. 16, 19, 21, 30, 46, 71, 107
(1) 19
(2) 21
(3) 30
(4) 46
(5) 71

3. 7, 9, 16, 25, 41, 68, 107, 173
(1) 107
(2) 16
(3) 41
(4) 68
(5) 25

4. 4, 2, 3.5, 7.5, 26.25, 118.125
(1) 118.125
(2) 26.25
(3) 3.5
(4) 2
(5) 7.5

5. 16, 4, 2, 1.5, 1.75, 1.875
(1) 1.875
(2) 1.75
(3) 1.5
(4) 2
(5) 4

6. 150, 290, 560, 1120, 2140, 4230, 8400
(1) 2140
(2) 560
(3) 1120
(4) 4230
(5) 290

7. 10, 8, 13, 35, 135, 671, 4007
(1) 8
(2) 671
(3) 135
(4) 13
(5) 35

8. 80, 42, 24, 13.5, 8.75, 6.375, 5.1875
(1) 8.75
(2) 13.5
(3) 24
(4) 6.375
(5) 42

9. 125, 75, 45, 25, 16.2, 9.72, 5.832
(1) 25
(2) 45
(3) 9.72
(4) 16.2
(5) 75

10. 29, 37, 21, 43, 13, 53, 5
(1) 37
(2) 53
(3) 13
(4) 21
(5) 43

11. 13, 25, 40, 57, 79, 103, 130
(1) 25
(2) 40
(3) 57
(4) 79
(5) None of these

12. 850, 600, 550, 500, 475, 462.5, 456.25
(1) 600
(2) 550
(3) 500
(4) 462.5
(5) None of these

13. 2, 10, 18, 54, 162, 486, 1458
(1) 18
(2) 54
(3) 162
(4) 10
(5) None of these

14. 8, 12, 24, 46, 72, 108, 152
(1) 12
(2) 24
(3) 46
(4) 72
(5) None of these

15. 142, 119, 100, 83, 65, 59, 52
(1) 65
(2) 100
(3) 59
(4) 119
(5) None of these

Solution