Matching principal and interest: monthly repayment amount = (loan principal × monthly interest rate× (1interest rate) total repayment period) /( 1 interest rate) total repayment period-1. Average capital: repayment of principal and interest in each period = loan principal/repayment times (loan principal-accumulated repayment amount) × number of periods.
Mortgage interest rate refers to the relevant mortgage loan amount. The mortgage interest rate is the monthly interest paid by applying for a loan from the bank in installments.