Question

Frank rented a truck for one day. There was a base fee of $20.99, and there was an additional charge of 86 cents for each mile driven. Frank had to pay $220.51 when he returned the truck. For how many miles did he drive the truck?

Answer 1

There are two types of associated costs, i.e. fixed cost and variable cost.

The fixed cost of renting the truck is given as $20.99, and the variable cost is the charge of per mile driven, given as 86 cents per mile (= $0.86 per mile).

Then the total cost of renting the truck is given by,

`\text{Total Cost=Fixed Cost+Variable Cost}`

Let 'x' be the number of miles driven.

Then the total variable cost is given by,

`\begin{gathered} \text{Variable cost=No. of miles}*\text{ Cost per mile} \\ \text{Variable cost=x}*\text{ 0}.86 \\ \text{Variable cost=0}.86x \end{gathered}`

Substitute the values,

`\begin{gathered} \text{220.51=20.99+0.86x} \\ 0.86x=220.51-20.99 \\ 0.86x=199.52 \\ x=(199.52)/(0.86) \\ x=232 \end{gathered}`

Thus, Frank drove the truck 232 miles.