Question

    Two inlets X, Y fill the tank in 18 and 9 minutes.

    Outlet Z is 50% less efficient than X. ‘X’ and ‘Z’ open for 6 minutes, then X is replaced with Y. Find total time to fill the tank.
    A 14 minutes Correct Answer Incorrect Answer
    B 16 minutes Correct Answer Incorrect Answer
    C 18 minutes Correct Answer Incorrect Answer
    D 20 minutes Correct Answer Incorrect Answer

    Solution

    Tank = 18x units
    X = x, Y = 2x, Z = 0.5x
    6 mins: (x - 0.5x) × 6 = 3x
    Remaining = 18x - 3x = 15x
    Net = 2x - 0.5x = 1.5x
    Time = 15x / 1.5x = 10 minutes
    Total = 6 + 10 = 16 minutes

    Practice Next
    More Pipes and cisterns Questions

    Relevant for Exams:

    ask-question