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

    Question

    If Rina can complete a project in 36 days by working 9

    hours a day, how many hours per day should she work to complete the project in 18 days?
    A 15 hrs Correct Answer Incorrect Answer
    B 18 hrs Correct Answer Incorrect Answer
    C 12 hrs Correct Answer Incorrect Answer
    D 24 hrs Correct Answer Incorrect Answer

    Solution

    ATQ,

    Let the efficiency of Rina be 'x' units per hour

    Therefore, total work = 9 × 36 × x = 324x units

    Let the time she should work to complete the work in 18 days be 'y' hours a day.

    ATQ;

    324x = 18 × y × x

    Or, y = 18

    Therefore, she should work for 18 hours a day.

    Alternate solution:

    Required time = (9 × 36) ÷ 18 = 18 hours

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