64. Calculating Interest Rates You are buying a house and will borrow $225,000 on a 30-year fixed rate mortgage with monthly payments to finance the purchase. Your loan officer has offered you a mortgage with an APR of 4.3 percent. Alternatively, she tells you that you can buy down the interest rate to 4.05 percent if you pay points up front on the loan. A point on a loan is 1 percent (one percentage point) of the loan value. How many points, at most, would you be willing to pay to buy down the interest rate?

excel functions please, with explanations

E F Chapter 6 Question 64 Input area: 360 Amount of loan # of years Interest rate Buydown rate 225,000 30 4.30% 4.05% Output area: Original monthly rate Buydown monthly rate Monthly payment at original rate PV of payments at new rate Dollar amount of points Maximum points