You need a 35-year, fixed-rate mortgage to buy a new home for $245,000. Your mortgage bank will lend you the money at an APR of 5.4 percent for this 420-month loan. However, you can afford monthly payments of only $850, so you offer to pay off any remaining loan balance at the end of the loan in the form of a single balloon payment.

How large will this balloon payment have to be for you to keep your monthly payments at $850?