A couple purchased a house 5 years ago for $300,000. The house was financed by paying 20% down and taking a 30-year fixed rate mortgage at 4.5% on the unpaid balance. The market value of the house is now $400,000. Assume that the couple wishes to sell the house.
(a) How much equity (to the nearest dollar) does the family have in the house now, after making 60 monthly payments?
(b) Find the first interest payment I1 and the 60th interest payment I60.