Problem
On the first of May 2015 Lee and Kim borrowed $250,000 from the Eastside Bank in order to buy an apartment. The loan was to be repaid through 180 monthly payments over a period of 15 years, with the first payment due on the first of June 2015, and each payment being the same size. The interest rate charged by the Eastside Bank was j12=5.04% p.a.
1. Determine the size of the monthly payments.
2. Determine the size of the outstanding principal immediately after Lee and Kim's 20th payment.