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    Question

    A series contains thirteen consecutive odd numbers. If the

    average of these numbers is 41, determine the ratio of the first number to the last number in the sequence.
    A 35:37 Correct Answer Incorrect Answer
    B 36:37 Correct Answer Incorrect Answer
    C 25:57 Correct Answer Incorrect Answer
    D 29:53 Correct Answer Incorrect Answer

    Solution

    ATQ,

    Let the first number of the series be ‘x’.

    2nd number will be = ‘x + 2’

    So, the series becomes:

    x, x + 2, x + 4, x + 6, x + 8, x + 10, x + 12, x + 14, x + 16, x + 18, x + 20, x + 22, x + 24

    Average of series = (x + x + 24)/2 = x + 12

    ATQ;

    41 = x + 12

    Or, x = 29

    So, the last (13th) number = x + 24 = 29 + 24 = 53

    Required ratio = 29:53

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