write a function rule for the total bill

Question

A car rental agency charges $33 per day to rent a car and $14.95 per day for a global positioning system (GPS). Customers are charged for their full tank of gas at $4.10 per gallon. A car has a 13 gallon tank and a GPS.
a) Write a function rule for the total bill b as a function of the days d the car is rented.
b) What is the bill for a 7 day rental?

Answer 1

b(d) = 33d + 14.95d + 13(4.1)

b(d) = 47.95d + 53.3

b(7) = 47.95(7) = 53.3

b (7) = 388.95