Problema Solution

a tank is filled in 9 hrs. and drained in 11 hours. HOw long wil it take to fill the tank if the drain is left half open?

Answer provided by our tutors

the filling rate if the tank is 1/9 tank per hour


the draining rate of the tank is 1/11 tank per hour


x = the hours needed for the tank to fill while the drain is open


1/9 + 1/11 = 1/x


by solving we find


x = 4.95 hr


click here to see the step by step solution of the equation


Click to see all the steps



x = 4 hr 57 min


if the drain is open the tank will fill in 4 hr 57 min.