Matching principal and interest method: loan principal: 3 10000, assuming annual interest rate: 4.900%, loan term: 10 year, monthly repayment of principal and interest: 3,272.9 yuan, total repayment: 392,748 yuan, * * interest payable: 82,748 yuan. The interest paid in 1 month is:1265.83; The repayment of principal in 1 month is July 2007; Since then, the monthly interest repayment amount has decreased and the principal has increased. (without considering the adjustment of interest rate in the middle)