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

    Question

    The average of the two numbers is 15, and the square

    root of their product is 12. What is the difference between the two numbers?
    A 12 Correct Answer Incorrect Answer
    B 10 Correct Answer Incorrect Answer
    C 15 Correct Answer Incorrect Answer
    D 18 Correct Answer Incorrect Answer

    Solution

    Let the two numbers = a and b          Given – Average of numbers = (a + b)/2 = 15 a + b = 30        ...(I) square root of these numbers = √  ab = 12 squaring both sides ab = 144 So now – (a + b)2 = (a- b)2 + 4ab (30)2 – 4 ×144 = (a-b)2 (a-b)2 =900- 576 = 324   a – b = 18

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