Matching principal and interest method: the total loan amount is 350,000 yuan, assuming that the annual interest rate was 4.900% and the loan period was 20 years. The monthly repayment amount of principal and interest is 2290.55 yuan, and the total repayment amount is 549732 yuan, * * interest payable 199732 yuan. The interest paid in the first month is 1429. 17, and the principal paid in the first month is 861.38; The interest paid in the second month is 1425.65 and the principal paid in the second month is 864.9. Since then, the monthly interest repayment amount has decreased and the principal has increased. (without considering the adjustment of interest rate in the middle)

The number of months returned is 120 months; * * * Pay the interest 14 182 1.93, * * Pay the principal 133044.07, pay the remaining principal 2 16955.93, and pay the interest of the last installment of 885.9 (regardless of the midway interest rate)