A tank is filled by three pipes A, B, C. A takes 10 hours, B takes 15 hours, C takes 20 hours to fill the tank. How long will it take to fill the tank if all three pipes are opened together?
Q1. A tank is filled by three pipes A, B, C. A takes 10 hours, B takes 15 hours, C takes 20 hours to fill the tank. How long will it take to fill the tank if all three pipes are opened together?
Answer: 4.6 hours
Explanation: Rate of A = 1 / 10, B = 1 / 15, C = 1 / 20. Combined rate = 1/10 + 1/15 + 1/20 = 13/60. Time = 60/13 = 4.6 hours.