lot parking is 3 dollars for the first half hour then its 1.25 for each hour after. there is partial hour charge that is the same as a full hour. Whats the longest time someone can park in the lot for 10 dollars.

1.25t+3<=10

-3 >= -3

1.25t<=7

1.25/1.25 <= 7/1.25

=5.6 + 1/2 (which is the first half hour)

I worked it out a bit, tell me if I got it, or help me if I'm close, thanks.