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What should come in place of the question mark (?) in the given series? 789 790 780 782 772 775 765?

A770

B755

C759

D768

Answer:

C. 759

Read Explanation:

Let’s look at the pattern:

Series: 789, 790, 780, 782, 772, 775, 765, ?

Split into alternating operations

We observe two interleaving patterns:

Odd positions:

789 → 780 → 772 → 765
Changes:

  • 789 − 9 = 780

  • 780 − 8 = 772

  • 772 − 7 = 765

So pattern: −9, −8, −7, −6

Next odd term is:
765 − 6 = 759

Even positions (just for confirmation):

790 → 782 → 775

  • −8, −7 (consistent decreasing pattern)

    Final term

The next term continues the odd-position pattern.

Final Answer: 759


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