Problema Solution

a pool can be filled by one pipe in 5 hours and by a second pipe in 6 hours. How long will it take using both pipes to fill the pool?

Answer provided by our tutors

in 1 hour first pipe will fill in 1/5

in 1 hour second pipe will fill 1/6

in hour both will fill   =  1/5 + 1/6  =  11/30

so it will be filled in

 

30/11   =  2 8/11  hours