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

    Question

    The average weight of 8 people is 75 kg. When three new

    people with their weights in the ratio 3:4:5 joined the group, the average weight of all the people remains the same. Find the difference between the weights of the lightest and the heaviest new people who joined the group.
    A 65.5 kg Correct Answer Incorrect Answer
    B 20.5 kg Correct Answer Incorrect Answer
    C 35.5 kg Correct Answer Incorrect Answer
    D 37.5 kg Correct Answer Incorrect Answer
    E none of these Correct Answer Incorrect Answer

    Solution

    ATQ, Sum of the weight of 8 people = 75 × 8 = 600 kg Sum of the weights of all the people including the ones who joined later = 75 × 11 = 825 kg Total weight of three new people = 825 - 600 = 225 kg Let the weights of the three new people who joined the group be '3y', '4y', and '5y' kg, respectively. 3y + 4y + 5y = 225 Or, 'y' = (225/12) = 18.75 So, required difference between the heaviest and the lightest = 5y - 3y = 2y = 2 × 18.75 = 37.5 kg

    Practice Next

    Relevant for Exams: