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


    Question

    Pipe β€˜A’ takes 20 hours to fill a tank. Pipe β€˜B’

    takes 80 hours to empty the same tank. If both are opened together, then how long will it take to fill 75% of the tank?
    A 20 hours Correct Answer Incorrect Answer
    B 18 hours Correct Answer Incorrect Answer
    C 19 hours Correct Answer Incorrect Answer
    D 21 hours Correct Answer Incorrect Answer

    Solution

    Let the capacity of the tank be 160 litres.So, efficiency of pipe β€˜A’ = 160 Γ· A = 8 litres/hour And efficiency of pipe β€˜B’ = 160 Γ· B = 2 litres/hour So, combined efficiency of both pipes = 8 – 2 = 6 litres/hour So, time taken to fill 75% of the tank = (160 Γ— 0.75) Γ· 6 = 120 Γ· 6 = 20 hours

    Practice Next
    ask-question