## 21, 9, 21, 11, 21, 13, 21, … What number should come next?

Table of Contents

A. 14

B. 15

C. 21

D. 23

## Answer & Solution

Answer:

**Option B**Solution:

In this alternating repetition series, the random number 21 is interpolated every other number into an otherwise simple addition series that increases by 2, beginning with the number 9.

# Also Read:

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