Which of the following numbers will replace the question mark (?) in the given series?
665, 670, 663, 674, 661, 678, ?, 682
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 659.
Given series: 665, 670, 663, 674, 661, 678, ?, 682
The series follows this pattern:
665 + 5 = 670
670 - 7 = 663
663 + 11 = 674
674 - 13 = 661
661 + 17 = 678
678 - 19 = 659
659 + 23 = 682
So, the missing term in the series is 659.