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What should come in place of the question mark (?) in the given series? 650 660 669 677 684 ?

A686

B688

C692

D690

Answer:

D. 690

Read Explanation:

Series: 650, 660, 669, 677, 684, ?

Step 1: Find the differences

Numbers

Difference

650 → 660

+10

660 → 669

+9

669 → 677

+8

677 → 684

+7

The pattern is decreasing by 1:
+10, +9, +8, +7, +6

Step 2: Add the next difference

684 + 6 = 690

Answer: 690


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