Parking in a student lot costs $1 for the first half hour and $1.50 for each hour thereafter. A partial hour is charged the same as a full hour. What is the longest time that a student can park in this lot for $7 ?

4.5 hours

Step-by-step explanation:

First subtract $7 - $1 for the first half hour to see how much money is left over

$7-$1 = $6 dollars left

$1.50 for each hour

6/1.50 = 4 hours

Don't forget the first half hour. So 4.5 hours