Question

The Hydro water department has a monthly service charge of $14.40 and a volume charge of $1.10 for every 100 cubic feet of water.

The total monthly cost is equal to the service charge plus the charge for the volume used during the month. If we let x represent the number of cubic feet of water (in hundreds) and y represent the total monthly cost, then we have:
total monthly cost = volume charge + service charge
y = 1.1x + 14.40

If the Johnson family used 200 ft3 less water this month than last month, then they can expect

Answer 1

an increase in their water bill of $28.80.
a decrease in their water bill of $2.20.
an increase in their water bill of $2.20.
a decrease in their water bill of $28.80.