Question

A 28,000-gallon swimming pool is being drained using a pump that empties 700 gallons per hour. Which equation models this situation if g is the number of gallons remaining in the pool and t is the amount of time in hours the pool has been draining?

28,000 = –700t
28,000g = –700t
g = 700t – 28,000
g = 28,000 – 700t

Answer 1

g = 28,000 − 700t

Reason: start with 28,000 gallons and subtract 700 gallons per hour times t. (The pool empties completely at t = 28,000/700 = 40 hours.)