Which of the following numbers will replace the question mark (?) in the given series?
11, 21, 16, 26, ?, 31
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 21.
Given series: 11, 21, 16, 26, ?, 31
11 + 10 = 21; 21 - 5 - 16; 16 + 10 = 26; 26 - 5 = 21; 21 + 10 = 31