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    ​Select the number that can replace the question mark (?) in the following series.9, 20, 42, 86, 174, 350, ?
    Question

    Select the number that can replace the question mark (?) in the following series.
    9, 20, 42, 86, 174, 350, ?

    A.

    702

    B.

    600

    C.

    720

    D.

    612

    Correct option is A

    Given: 9, 20, 42, 86, 174, 350, ?
    Logic: Each term is obtained by multiplying the previous term by 2 and then adding 2.
    According to the logic-
    Thus, the correct answer is (a) 702

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