Question

Which of the following numbers will replace the question mark (?) in the given series? 7, 20, 37, 56, 79, 108,?

• A. 122
• B. 126
• C. 136
• D. 139

Answer 1

Answer:

D. 139

The number 139 will replace the question mark in the series.

The series increases by adding consecutive prime numbers starting from 13:

* 7 + 13 = 20

* 20 + 17 = 37

* 37 + 19 = 56

* 56 + 23 = 79

* 79 + 29 = 108

Following this pattern, the next prime number after 29 is 31:

* 108 + 31 = 139