Question

There are 3 pipes connected to a tank.Pipe a and pipe b are the fill pipes while pipe c is an empty pipe that can empty the full tank in 12 hours.Pipe a is 80% more efficient than



b.If all the pipes are opened simultaneously then the tank is filled in 180/13 hours.Find the time in which pipes a and b together can fill the tank when pipe c is closed for whole time

Answer 1

Let A take x hours to fill the tank.
B takes 5x/9 hours to fill the tank
C takes 12 hours to empty the tank
If all these are in operation 1/x+9/5x-1/12 th part can be filled by three in 1 hour =(168-5x)/60x
Total time required =60x/(168-5x)=183/13
X=18
A can fill in 18 hours & B can fill in 10 hours
A&B together can fill 1/18+1/10=7/45
Required time to fill the tank is 45 /7 hours

Answer 2

Answer:

45/7

Step-by-step explanation:

Let A take x hours to fill the tank.

B takes 5x/9 hours to fill the tank

C takes 12 hours to empty the tank

If all these are in operation 1/x+9/5x-1/12 th part can be filled by three in 1 hour =(168-5x)/60x

Total time required =60x/(168-5x)=183/13

X=18

A can fill in 18 hours & B can fill in 10 hours

A&B together can fill 1/18+1/10=7/45

Required time to fill the tank is 45 /7 hours