Question

    A single tap takes 12 hours to fill the entire tank.

    Initially, only one tap is open, and it fills half of the tank. At that point, four additional identical taps are turned on. How much total time is required to completely fill the tank?
    A 2.5 hrs Correct Answer Incorrect Answer
    B 5.5 hrs Correct Answer Incorrect Answer
    C 8.5 hrs Correct Answer Incorrect Answer
    D 7.2 hrs Correct Answer Incorrect Answer

    Solution

    ATQ,
    The first tap alone fills half the tank in 12/2 = 6 hours.
    With 5 taps running, the remaining half is filled in (1/2) × (12/5) = 1.2 hours.
    Total time = 6 + 1.2 = 7.2 hours.

    Practice Next