New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    The average of 19 numbers is 15.The average of first 9

    numbers are12 and that of the last 9 numbers are15. What will be the 19th number?
    A 30 Correct Answer Incorrect Answer
    B 57 Correct Answer Incorrect Answer
    C 42 Correct Answer Incorrect Answer
    D 66 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Sum of 19 numbers = 19 ×15 = 285 Sum of first 9 numbers = 9×12 = 108 Sum of last 9 numbers = 9×15 = 135 Therefore, 19thnumber = 285 – (108 + 135) = 42

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