Best Rentals charges a daily fee plus a mileage fee for renting its cars. Barney was charged $111.00 for 3 days and 300 miles, while Mary was charged $198.00 for 5 days and 600 miles. What does Best Rentals charge per day and per mile?

3d+300m = 111

5d+600m = 198

Now just solve for d and m

To find the daily fee and mileage fee charged by Best Rentals, we can set up a system of equations based on the given information.

Let's say the daily fee is represented by "d" and the mileage fee is represented by "m" (in dollar amounts).

Based on the information given for Barney's rental:
3d + 300m = 111 (equation 1)

And based on the information given for Mary's rental:
5d + 600m = 198 (equation 2)

We now have a system of two equations. We can solve this system of equations using either substitution or elimination method to find the values of "d" and "m".

Let's use the elimination method to solve the system of equations:
Multiply both sides of equation 1 by 5, and equation 2 by 3 to make the coefficients of "d" in both equations the same:
15d + 1500m = 555 (equation 3)
15d + 1800m = 594 (equation 4)

Now, subtract equation 4 from equation 3 to eliminate "d":
(15d + 1500m) - (15d + 1800m) = 555 - 594
15d - 15d + 1500m - 1800m = -39
-300m = -39

Divide both sides of the equation by -300:
m = (-39) / (-300)
m = 0.13

So, the mileage fee charged by Best Rentals is $0.13 per mile.

Now, substitute the value of "m" into equation 1 to find the value of "d":
3d + 300(0.13) = 111
3d + 39 = 111
3d = 111 - 39
3d = 72

Divide both sides of the equation by 3:
d = 72 / 3
d = 24

So, the daily fee charged by Best Rentals is $24 per day.

Therefore, Best Rentals charges $24 per day and $0.13 per mile.