Jerry bought a house for $400,000 and made an $80,000 down payment. He obtained a 30-year loan for the remaining amount. Payments were made monthly. the nominal annual interest rate was 6% after 10 years (120 payments) he sold the house and paid the remainder of the loan balance.
What is the present worth of the annuity of 240 (or what must he have paid in addition to the 120th month payment to pay off the loan)?