1. To model the relationship between the parking hours and the cost, we can use the following equation:

Here,
represents the cost
as a function of the parking hours
.
2. To calculate how much you have to pay for parking for 10 hours, we can substitute
into the equation:

Therefore, you would have to pay $7.00 to park for 10 hours.
3. To find out how many hours $10 can buy, we need to solve the equation:

Simplifying the equation:


Dividing both sides of the equation by 0.25:


Adding 2 to both sides of the equation:

Therefore, $10 would buy you 22 hours of parking.
To clarify, the answer is 22 hours, not 20 hours.