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What should come in place of the question mark (?) in the given series? 673 670 664 655 643 ?

A632

B625

C628

D630

Answer:

C. 628

Read Explanation:

Look at the pattern in differences:

  • 673 → 670 = −3

  • 670 → 664 = −6

  • 664 → 655 = −9

  • 655 → 643 = −12

The differences are increasing by −3 each time.

So next difference = −15

643 - 15 = 628

Answer: 628


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