A 18-year loan of 19,500 may be repaid under the following two methods:
amortization method with equal annual payments at an annual effective rate of 6.3%
sinking fund method in which the lender receives an annual effective rate of 6.750% and the sinking fund earns an annual effective rate of j.
Both methods require a payment of X to be made at the end of each year for 18 years. Calculate j.