Jon's laundry machine can do 5 pounds of laundry at a time.  4 shirts weigh 1 pound and 2 pairs of pants weigh 1 pound.  If he needs to wash 20 shirts and 20 pants, how many loads of laundry does he have to do?
The shirts weigh 20/4=<T>divide(20, 4)=5.0 pounds
The pants weigh 20/2=<T>divide(20, 2)=10.0 pounds
So he needs to do 10+5=<T>add(10, 5)=15 pounds of laundry
So that would take 15/5=<T>divide(15, 5)=3.0 loads of laundry
