Chapter 9.5, Problem 46CCR

To determine

To write an equation and find the unit cost of the gas.

Answer to Problem 46CCR

The equation to find the unit cost of gas is, $\text{Unit Cost of gas}=\frac{\text{Total cost of gas}}{\text{Quantity of gas}}$

The unit cost of the gas is $\$2.75$ .

Explanation of Solution

Given information:

The given statement is:

The cost of gas varies directly with the number of gallons bought. Marty bought $18\text{ gallons}$ of gas for $\$49.50$ . Write an equation that could be used to find the unit cost of the gallon of gas. Then find the unit cost.”

Calculation:

The equation to find the unit cost of gas is written by:

  $\text{Unit Cost of gas}=\frac{\text{Total cost of gas}}{\text{Quantity of gas}}$

The unit cost of the gas can be calculated by:

  $\begin{array}{l}\text{Unit Cost of gas}=\frac{\text{Total cost of gas}}{\text{Quantity of gas}}\\ \text{Unit Cost of gas}=\frac{\text{\$49}\text{.50}}{\text{18 gallons}}\\ \text{Unit Cost of gas}=\$2.75\end{array}$

Hence, the unit cost of the gas is $\$2.75$ .