πŸ“’ Too many exams? Don’t know which one suits you best? Book Your Free Expert πŸ‘‰ call Now!


    Question

    Pipe P can fill a tank by itself

    in 16 hours, while pipe R can empty the tank in 36 hours when it is full. Together, pipes P and Q can fill the tank in 9 hours. How long will it take for pipes Q and R, working together, to fill the same tank?
    A 58 hrs Correct Answer Incorrect Answer
    B 48 hrs Correct Answer Incorrect Answer
    C 38 hrs Correct Answer Incorrect Answer
    D 28 hrs Correct Answer Incorrect Answer

    Solution

    ATQ, Let the capacity of the tank = L.C.M of 16 and 36 = 144 units Then, efficiency of pipe β€˜P’ alone = 144 Γ· 16 = 9 units/hour Efficiency of pipe β€˜R’ alone = 144 Γ· 36 = 4 units/hour Combined efficiency of pipes β€˜P’ and β€˜Q’ = 144 Γ· 9 = 16 units/hour So, efficiency of pipe β€˜Q’ alone = 16 – 9 = 7 units/hour So, combined efficiency of pipes β€˜Q’ and β€˜R’ = 7 – 4 = 3 units/hour So, time taken by pipes β€˜Q’ and β€˜R’ together to ill the tank = 144 Γ· 3 = 48 hours.

    Practice Next

    Relevant for Exams:

    ask-question

    Not sure which exam is best for you Talk to our expert

    Get My Free Call