Problema Solution

at a diary plant, a milk tank can be filled in 6 hours(using the in-valve). Using the out-valve, the can be emptied in 10 hours. If both valves are open and milk is being pumped into the tank, how long will it take to fill the tank?

Answer provided by our tutors

filled in 6 hrs

emptied in 10 hrs

Both valves open then it will fill in 1 hrs (1/6)-(1/10)= 1/15 

1/15 part in 1 hrs 

so in full part in 15hrs