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    Select the number from among the given options that can replace the question mark (?) in the following series. 7 : 56 :: 8 : 72 :: 9 : ?
    Question

    Select the number from among the given options that can replace the question mark (?) in the following series.
    7 : 56 :: 8 : 72 :: 9 : ?

    A.

    100

    B.

    90

    C.

    99

    D.

    81

    Correct option is B

    Given: 7 : 56 :: 8 : 72 :: 9 : ?
    Logic: The pattern follows N (N+1);  Where N is the first number in each pair (7, 8, 9)
    Applying it to the given numbers:
    7×(7+1)=7×8=56
    8×(8+1)=8×9=72
    9×(9+1)=9×10= 90
    Thus, the correct option is (b) 90

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