Question

Pipe A and Pipe B can fill a cistern in 10 hours and 15 hours respectively. When a third pipe C which works as an
outlet pipe is also open then the cistern can be filled in 18 hours. The outlet pipe can empty a full cistern in:

Answer 1

Answer:

20 hours

Step-by-step explanation:

Pipe A can fill in 12 hrs.

Pipe B can fill in 15 hrs.

Pipe C can empty in 10 hrs.

In one hour, the pipe A can fill 112 part

In one hour, the pipe B can fill. 115 part.

In one hour, the pipe C can empty 110 part.

If all the three open together A B C can fill (112+115−110) part

= 5+4−660=360=120 part

The tank can be filled in 20 hours