Donna is filling a tank with water at a rate of
gallons per minute. The tank already had
gallons of water in it. Suppose the tank holds a total of
gallons of water. How much longer will it take her to fill the tank?
Since the tank holds 200 gallons ad it has 140 gallons in it, there are only 200-140 = 60 gallons left to fill.
60 galllons/ 2gal/min = 30 minutes