SOLUTION: it takes 30 minutes to fill a water tank, when no one is using water. when people use water or filled tank is emptied in 4 hrours. how log does it take to fill the tank while the w

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons  -> Linear Equations Lesson -> SOLUTION: it takes 30 minutes to fill a water tank, when no one is using water. when people use water or filled tank is emptied in 4 hrours. how log does it take to fill the tank while the w      Log On


   

Question 948297: it takes 30 minutes to fill a water tank, when no one is using water. when people use water or filled tank is emptied in 4 hrours. how log does it take to fill the tank while the water is being used?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Find the SUM of the two rates. Note that the signs of the two rates are opposite, and you must arrange both rates as TANKS PER MINUTE, or as TANKS per HOUR.

1%2F%281%2F2%29-1%2F%284%29, this is for TANKS per HOUR.

The reciprocal of that expression will be unit of HOURS per TANK.