### Home > A2C > Chapter 8 > Lesson 8.1.4 > Problem 8-61

8-61.

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.