Select the number that can replace the question mark (?) in the following series.
15, 18, 13, 20, 11, ?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 22
- Series is 15, 18, 13, 20, 11, ?
- The pattern is on the two-part first
- 15 - 2 = 13, 13 - 2 = 11 and so on.
- Second part is 18 + 2 = 20, 20 + 2 = 22
- Hence, the correct answer is option 3.