# Logical Reasoning - Number Series

### Exercise :: Number Series - Type 2

Look carefully for the pattern, and then choose which pair of numbers comes next.
16.

9 12 11 14 13 16 15

 A. 14 13 B. 18 21 C. 14 17 D. 12 13 E. 18 17

Explanation:

This is a simple alternating addition and subtraction series. First, 3 is added, then 1 is subtracted, then 3 is added, 1 subtracted, and so on.

17.

4 8 22 12 16 22 20 24

 A. 28 32 B. 28 22 C. 22 28 D. 32 36 E. 22 26

Explanation:

This is an alternating repetition series, with a random number, 22, interpolated as every third number into an otherwise simple addition series. In the addition series, 4 is added to each number to arrive at the next number.

18.

40 40 31 31 22 22 13

 A. 13 4 B. 13 5 C. 4 13 D. 9 4 E. 4 4

Explanation:

This is a subtraction series with repetition. Each number repeats itself and then decreases by 9.

19.

1 10 7 20 13 30 19

 A. 26 40 B. 29 36 C. 40 25 D. 25 31 E. 40 50

Explanation:

Here, every other number follows a different pattern. In the first series, 6 is added to each number to arrive at the next. In the second series, 10 is added to each number to arrive at the next.

20.

10 20 25 35 40 50 55

 A. 70 65 B. 60 70 C. 60 75 D. 60 65 E. 65 70