Parking garage charges $1.00 for first half hour and $0.60 for each additional half hour. Write an equation and solve to find how long you can park with $6.00.

c(t)=1.00+0.60t   if t>1 hr

For c(t)=$6.00 we get:

6=1+.6t
5=.6t
t=5/0.6

t=8 1/3 hours (8 hrs 20 min)