Question

A watering can dispenses water at the rate of 0.20 gallon per minute. The original volume of water in the can was 8 gallons. Which set of ordered pairs shows the volume of water in the can in gallons (y), as a function of time in minutes (x), from the first minute after can starts dispensing water?

Answer 1

The formula for the volume of water in the can at time x is given by

v(x) = 8 gal - (0.2 gal / min)x.
At the beginning, v(0) = 8 gal.
One min. later, v(1) = (8-0.2) gal.

and so on.
After 1 min, (1,7.8) represents the vol of water left in the can.