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

    Question

    Average of 20 numbers is 90. Average of first 8 numbers

    is 114 while average of last nine numbers is 40. If ninth number is 25% less than the tenth number which is equal to the eleventh numbers then find the tenth number.
    A 122 Correct Answer Incorrect Answer
    B 182 Correct Answer Incorrect Answer
    C 172 Correct Answer Incorrect Answer
    D 192 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Sum of ninth, tenth and eleventh number = 20 × 90 – 8 × 114 – 9 × 40 = 528 Let tenth number = x = eleventh number So, ninth number = 0.75 × x = 0.75x So, x + 0.75x + x = 528 Or, 2.75x = 528 Or, x = 192

    Practice Next

    Relevant for Exams: