A tank is filled by two pipes where one pipe fills it three times faster than the other. If both pipes working together fill the tank in 36 minutes, how long will it take the slower pipe to fill the tank by itself?

Explanation

Let the slower pipe fill the tank in x minutes. The faster pipe, being three times quicker, fills it in x/3 minutes. Their combined rate is 1/x + 1/(x/3) = 1/36. Simplifying, (1/x) + (3/x) = 1/36, which gives 4/x = 1/36. Solving for x yields x = 144 minutes. Therefore, the slower pipe alone takes 144 minutes to fill the tank.