general math MCQ #57

Two pipes can separately fill a tank in 20 and 30 hours respectively. Both the pipes are opened to fill the tank but when the tank is full, a leak develops in the tank through which one-third of water supplied by both the pipes goes out. What is the total time taken to fill

general math MCQ #57

  1. Question 1

    Q1. Two pipes can separately fill a tank in 20 and 30 hours respectively. Both the pipes are opened to fill the tank but when the tank is full, a leak develops in the tank through which one-third of water supplied by both the pipes goes out. What is the total time taken to fill

    • A) 18 hrs
    • B) 16 hrs
    • C) 15 hrs
    • D) 12 hrs

    Answer: 18 hrs

    Explanation: Combined fill rate = 1/20 + 1/30 = 1/12; with 1/3 leaking, effective rate = 2/3 × 1/12 = 1/18; time = 18 hours.