Question

Meredith needs to rent a car while on vacation. The rental company charges $18.95, plus 18 cents for each mile driven. If Meredith only has $40 to spend on the car rental, what is the maximum number of miles she can drive? Meredith can drive a maximum of miles without the cost of the rental going over $40.Round your answer to the nearest mile.

Answer 1

117 miles

Explanation:

First we need an equation for the situation. The number of miles is our unknown, x. If she is charged 18 cents per mile, that can be expressed as .18x. The flat rate, what she is charged regardless of how many miles she drives, is 18.95. In other words, even if she drives 0 miles, she is still charged 18.95 for the rental of the car. C(x) is the amount she will pay after the flat rate plus the number of miles she drives. Therefore, our equation is:

C(x) = .18x + 18.95

If she can only spend 40, then we replace C(x) with 40 and solve for x, the number of miles:

40 = .18x + 18.95

Begin by subtracting 18.95 from both sides to get:

21.05 = .18x

Now divide both sides by .18 to get that

x = 116.9 miles

Rounding, we have that she can drive

117 miles

with the amount of money she has to spend on a rental car.