Question

    The average weight of 6 students in a group is 45 kg. If

    one student is replaced by person 'B', the average weight of the group increases by 5%. Find the difference between the weight of the student who left and the weight of person 'B'.
    A 13.5 kg Correct Answer Incorrect Answer
    B 25.5 kg Correct Answer Incorrect Answer
    C 53.5 kg Correct Answer Incorrect Answer
    D 32.4 kg Correct Answer Incorrect Answer

    Solution

    ATQ,

    Total weight of the group = 45 × 6 = 270 kg

    New average weight of the group = 45 × 1.05 = 47.25 kg

    So, total weight of the group = 47.25 × 6 = 283.5 kg

    So, difference between weights of the student who left and person 'B' =
    283.5 - 270 = 13.5 kg

    Alternate Solution—

    Required difference = 0.05 × 45 × 6 = 13.5 kg

    Practice Next

    Relevant for Exams: