Matching principal and interest method: loan principal: 65,438+040,000, assuming annual interest rate: 4.900%, loan life: 65,438+00 years; Monthly repayment of principal and interest: 65,438+0,478.08 yuan, and total repayment of principal and interest: 65,438+0,773,69.6 yuan, * *. The interest paid in 1 month is: 571.67; The first 1 month principal repayment is: 906.4438+0; Since then, the monthly interest repayment amount has decreased and the principal has increased. (without considering the adjustment of interest rate in the middle)