Question

pipe A can fill a tank in 45 hours and pipe B can empty it in 36 hours.if both the pipes are opened in the empty tank, how many hours will it be full?​

Answer 1

Answer:

180 hrs

Step-by-step explanation:

Let the capacity of the tank be 180 L (LCM of 45,36).

Pipe A will add 4 L per hour and Pipe B will remove 5 L per hour. So, net work is 4 L - 5 L = -1 L. If the tank is initially empty, the tank will never get filled. If the tank is initially full, and both are open, tank will get empty after 180 hours.