Final answer:
The cost of a 3-day car rental can be calculated using the equation: Total Cost = (3 * 25) + (m * 8), where m is the number of miles driven.
Step-by-step explanation:
To calculate the cost of a 3-day car rental as a function of the number of miles driven, we need to consider both the daily rental fee and the mileage charge. The daily rental fee is $25 per day, so for a 3-day rental, the total rental fee would be 3 times $25. The mileage charge is 8 per mile, so for a certain number of miles driven, the total mileage charge would be the number of miles driven times 8. To calculate the total cost, we need to add the rental fee and the mileage charge:
Total Cost = (3 imes 25) + (m imes 8)
where m is the number of miles driven.