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    What should come in place of the question mark (?) in the given series? 591, 592, 596, 605, 621, ?
    Question

    What should come in place of the question mark (?) in the given series?
    591, 592, 596, 605, 621, ?

    A.

    641

    B.

    636

    C.

    646

    D.

    631

    Correct option is C

    Given:
    591 592 596 605 621 ?

    Logic:
    To find the next number, observe the differences between consecutive terms:
    592 − 591 = 1
    596 − 592 = 4
    605 − 596 = 9
    621 − 605 = 16
    The differences are: 1, 4, 9, 16, which are perfect squares (1², 2², 3², 4²).
    Now, following this pattern, the next difference should be 5² = 25.

    Explanation:
    621 + 25 = 646

    Final Answer:
    646

    Final Correct Option:
    (C) 646

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