Matching principal and interest method: suppose the annual interest rate at that time was 6.550% and the total loan amount was 1 13000. Loan term 15: the monthly repayment amount of principal and interest is 987.46 yuan, the total repayment amount is 177742.8 yuan, and the interest payable is 64,742.8 yuan. The interest paid in the first month is 6 16.79, and the principal paid in the first month is 370.67; The interest paid in the second month is 6 14.77, and the principal paid in the second month is 372.69. Since then, the monthly interest repayment amount has decreased and the principal has increased. (without considering the adjustment of interest rate in the middle)

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The number of return months is 36 months; * * * Pay the interest of 20847.46, * * Pay the principal 1470 1. 1, the remaining principal is 98298.9, and the last interest is 536.55 (without considering the adjustment of the intermediate interest rate)//Now it needs to be paid off: ￥98835.45.