Answer:
- C = 0.97m
- $1164 for 1200 miles
- 845 miles for $820
Explanation:
Given a car's cost of operation is $485 for 500 miles, you want an equation relating cost for m miles, and solutions to that equation for 1200 miles, and for a cost of $820.
Cost per mile
The cost per mile is found by dividing the cost by the associated number of miles:
$485/(500 mi) = $0.97 /mi
Equation
The equation for the cost will show the cost as the cost per mile multiplied by the number of miles:
C = 0.97m . . . . . where C is cost in dollars for m miles driven
1200 miles
The cost for driving $1200 miles will be ...
C = 0.97(1200) = $1164
The cost of driving 1200 miles is $1164.
$820
The number of miles that can be driven for a cost of $820 is ...
820 = 0.97m
m = 820/0.97 = 845.36
About 845 miles are driven for a cost of $820.