Write a equation for total monthly car costs as a function of miles driven in a month.

Question

Mary Ellen is trying to decide whether or not she can afford to purchase a car. She determines that it costs 22 cents per mile to drive her car, plus a fixed monthly cost of $230 for car payments and insurance.

Answer 1

let 'm' = mile driven in one month

let 22 cents be shown as a dollar decimal... .22

let '230' = $230 fixed monthly cost per month

 

equation reads:   .22m + 230 = cost/month

 

if Mary Ellen drives 100 miles in a month, equation will read:

.22(100) + 230 = cost/month    simplified to....

22 + 230 = $252 = cost/month

 

if Mary Ellen drives 188 miles in a month, equation will read:

.22(188) + 230 = cost/month   simplified to...

41.36 + 230 = $271.36 = cost/month