Home > CCA > Chapter A > Lesson A.1.6 > ProblemA-64

A-64.

One of Teddy’s jobs at home is to pump gas for his family’s sedan and truck. When he fills the truck up with 12 gallons of gas, he notices that it costs him $\39.48$. Homework Help ✎

1. How much does one gallon of gas cost? Explain how you found your answer.

One way to solve this problem is to set up a proportion.
Try using the proportion provided below.

$\frac{39.48}{12\text{ gals}}=\frac{\textit{n}}{1\text{ gal}}$

Multiply both sides by 12 gallons and then solve.

39.48 = 12n

3.29 = n

2. How much will it cost him to fill up the sedan if it needs 15 gallons of gas? Show your work.

Multiply the price per gallon by the number of gallons.

3. When Teddy filled up the tank on his moped, it cost $13.16. How much gas did his moped need? Explain how you know. Use a proportion to show the known price ($13.16) over the unknown number of gallons and follow the strategy shown in part (a) to solve.