A family wants to purchase a house that costs $120,000. They plan to take out a $100,000 mortgage on the house and put $20,000 as a down payment. The bank informs them that with a 15-year mortgage their monthly payment would be $796.78 and with a 30-year mortgage their monthly payment would be $517.05. Determine the amount they would save on the cost of the house if they selected the 15-year mortgage rather than the 30-year mortgage. How much would they save if they selected the 15-year mortgage?