The Butlers bought a $332,000 house. They made a down payment of 42,000 and took out a mortgage for the rest. Over the course of 15 years they made monthly payments of $2,447.19 on their mortgage until it was paid off.
(a) What was the total amount they ended up paying for the house (including the down payment and monthly payments)?
(b) How much interest did they pay on the mortgage?