Which number will replace the question mark (?) in the following series?
75, 76, 72, 81, 65, ?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1, i.e., 90.
75 + 1 = 76, 76 - 4 = 72, 72 + 9 = 81, 81 - 16 = 65, 65 + 25 = 90