A swimming pool has (e) gallons of water. the owner wants to drain the water to clean the pool. His water pumping machine can pump (f) gallons for every hour of use. Enter an equation for the amount of water remaining, (g) in the pool after (h) hours.

His pool starts with 20,000 gallons in it. His pump can move 500 gallons per hour.
Rewrite the equation with this new information.

How long will it take him to drain the pool?