Question

In one oty, the cost for water is $8.64 per 100 cubic feet of water. According to a study, the average shower in this city lasts 72 minutes and uses 19.1 gallons. A person showers once a day for a year. Find the total cost per year. Use theconversion factor of 7.48 gallons per cubic footThe total cost per year is $(Simplify your answer. Round to the nearest cent as needed. Do not include the $ symbol in your answer.)Enter your answer in the answer box

Answer 1

Annual cost for water

What do we know?

100 ft³ of water costs $8.64

The average shower in this city uses 19.1 gallons

A person showers once a day for a year.

7.48 gallons = 1 ft³

Cost per year = ?

Procedure

We first want to know how many gallons are equivalent to 100 ft³

Since 1 ft³ = 7.48 gallons if we multiply by 100 both sides, then

100 ft³ = 748 gallons

Then, 748 gallons of water costs $8.64

Secondly, we are finding how much a single shower costs.

Since the average shower uses 19.1 gallons, we find the cost of 19.1 gallon

We have the equivalences, then we divide both sides:

`(19.1)/(748)=\frac{\text{?}}{8.64}`

then, clearing the unknown quatity

`\begin{gathered} ?=8.64\cdot(19.1)/(748) \\ \text{?}=0.221 \end{gathered}`

Then, the cost of one shower is $0.221