Jan buys 1000 feet of cable.  She splits it up into 25-foot sections.  She gives 1/4 of that to a friend.  She then puts half of the rest in storage. How much does she keep on hand?
She gets 1000/25=<T>divide(1000, 25)=40.0 sections
She gives away 40/4=<T>divide(40, 4)=10.0 sections
So she keeps 40-10=<T>subtract(40, 10)=30 sections
She keeps 30/2=<T>divide(30, 2)=15.0 sections on hand
