Answer:
c = 25h + 30 or c(h) = 25h + 30
where h is hours and c is total cost
Explanation:
You (or someone, a ski-enthusiast) has to rent gear for $30. You do that first and you have to because you can't ski without gear. Even if you haven't skied any hours at all, you have to start with paying $30.
Then the hourly cost depends on how many hours. 1 hour, $25. 2hours, $50. 3 hours, $75, etc.
You multiply the number of hours times $25.
Add up your rental fees and your hourly cost and you get the total cost.
c = 25h + 30