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

    Question

    The average of fifty numbers is 55 while the average of

    first twenty-five numbers and last twenty-five numbers is 60 and 70, respectively. Find the twenty-fifth term.
    A 500 Correct Answer Incorrect Answer
    B 620 Correct Answer Incorrect Answer
    C 487 Correct Answer Incorrect Answer
    D 785 Correct Answer Incorrect Answer

    Solution

    ATQ,

    Sum of fifty numbers = (50 × 55) = 2750

    Sum of the first twenty-five numbers = (25 × 60) = 1500

    Sum of the last twenty-five numbers = (25 × 70) = 1750

    So, twenty-fifth term = 1500 + 1750 - 2750 = 500

    Practice Next

    Relevant for Exams: