Question

There is a tank, and two pipes a and

b. a can fill the tank in 25 min and b can empty the tank in 20 min. if both the pipes are opened at same time. how much time required for the tank to be filled?

Answer 1

Answer:

answer = 100 min

Step-by-step explanation:

A filled tank in 20 min therefore workdone in 1 min =1/20

B emptied tank in 25min therefore workdone by B in 1 min =1/25

now as A and B are working Against each other

1/20 - 1/25 =(25-20)/(20*25)

5/500

=1/100

therefore tank filled in 100 min.