Select the number from among the given options that can replace the question mark (?) in the following series.
6 ,7, 9, 13, 21, ?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 37.
Given: 6, 7, 9, 13, 21, ?
6 + 1 = 7, 7 + 2 = 9, 9 + 4 = 13, 13 + 8 = 21, 21 + 16 = 37