John needs to take 2 pills a day.  One pill costs $1.5.  The insurance covers 40% of the cost.  How much does he pay in a 30-day month?
It cost 2*1.5=$<T>multiply(2, 1.5)=3.0 a day.
So it cost 3*30=$<T>multiply(3, 30)=90 per day.
Insurance covers 90*.4=$<T>multiply(90, 0.4)=36.0
So he pays 90-36=$<T>subtract(90, 36)=54 a month.
