### Home > INT3 > Chapter 9 > Lesson 9.2.4 > Problem 9-142

9-142.

Rip-Off Rentals charges $25 per day plus 50¢ per mile to rent a mid-sized car. Your teacher will rent you his or her family sedan and charge you only 3¢ if you drive one mile, 6¢ if you drive two miles, 12¢ if you drive three miles, 24¢ for four miles, and so on. Homework Help ✎

Write equations that will allow you to calculate the cost of renting each car.

If you plan to rent the car for a two-day road trip, which is the better deal if you drive 10 miles? 20 miles? 100 miles?

Let *d* = number of days, *m* = number of miles, and *y* = total cost.

Your teacher is using a geometric sequence.

*y* = 25*d* + 0.5*m* and *y* = 0.03(2)^{m}^{−1}

Substitute the values into each equation to see which rental costs less for each distance.