Question

Jenn recently took a road trip. She bought 15 gallons of gasoline for $1.68 per gallon and 12 gallons at a price of $1.76 per gallon. She filled her tank once on the way back with 16 gallons at $1.65 per gallon. What was the average fuel cost per gallon on Jenn’s trip?

Answer 1

Jenn bought 15 gallons of gasoline for $1.68 per gallon

12 gallons at a price of $1.76 per gallon

16 gallons at $1.65 per gallon

Total fuel cost is

`\begin{gathered} \text{Total cost of fuel}=(15*1.68)+(12*1.76)+(16*1.65) \\ \text{Total cost of fuel}=25.2+21.12+26.4=\text{ \$72.72} \end{gathered}`

Total number of gallons is

`\text{Total number of gallons}=15+12+16=43`

The formula to find the average fuel cost is

`\text{Average fuel cost}=\frac{Total\text{ fuel cost}}{Total\text{ number of gallons}}`

Substitute the values into the formula of the average fuel cost

`\begin{gathered} \text{Average fuel cost}=\frac{Total\text{ fuel cost}}{Total\text{ number of gallons}} \\ \text{Average fuel cost}=(72.72)/(43)=\text{ \$1.69 (two decimal places)} \end{gathered}`

Hence, the average fuel cost is $1.69 (two decimal places)