To rent a midsize car for one day, Tom's Car Rentals charges a fee of $0.25 per mile driven. Write an equation that relates the total cost of the car rental for one day, T(m), as a function of the number of miles driven, m.
It's gonna be 0.25m because the fee is 25¢ but you are given a variable for the unknown quantity. Since you don't know how many miles he drove, you multiply m by the fee.