John buys 1.5 ounces of silver and twice as much gold.  The silver costs $20 per ounce.  The gold is 50 times more expensive per ounce.  How much does he spend on everything?
He buys the silver for 1.5*$20=$<T>multiply(1.5, 20)=30.0
He bought 1.5*2=<T>multiply(1.5, 2)=3.0 ounces of gold
The gold is worth %20*50=$<T>multiply(20, 50)=1000 per ounce
So he buys 3*$1000=$<T>multiply(3, 1000)=3000 on gold
So he spent $30+$3000=$<T>add(30, 3000)=3030 on everything
