A tank is filled by three pipes, A, B, and C. A fills 1/3 of the tank in 1 hour, B fills 1/4 of the tank in 1 hour, and C fills 1/6 of the tank in 1 hour. How long will it take to fill the tank?
Q1. A tank is filled by three pipes, A, B, and C. A fills 1/3 of the tank in 1 hour, B fills 1/4 of the tank in 1 hour, and C fills 1/6 of the tank in 1 hour. How long will it take to fill the tank?
Answer: 2 hours
Explanation: The combined rate of filling = 1/3 + 1/4 + 1/6 = (4 + 3 + 2)/12 = 9/12 = 3/4 of the tank per hour.