Matching principal and interest method: the total loan amount is 170000, assuming the annual interest rate at that time is 6.800%. The loan term is 20 years: the monthly repayment amount of principal and interest is 1297.68 yuan, the total repayment amount is 3 1 1443.2 yuan, and the * * repayable interest is 12 yuan. The interest paid in the first month is 963.33 and the principal paid in the first month is 334.35. The interest paid in the second month is 96 1.44, and the principal paid in the second month is 336.24; 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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It's been five years.

The number of return months is 60 months; * * * Pay the interest of 54,047.69, * * Pay the principal of 23813.1,the remaining principal of 146 186.89, and the interest of the last installment of 828.39 (regardless of the interest rate adjustment factor).

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Repay the principal in advance: 50,000 yuan, the remaining principal is 96 187, the annual interest rate is 0.049, and the loan period is15; . Monthly repayment amount: 755.64, total repayment amount 1360 15.2, and total interest amount of 39,828.2.