7. When we make monthly payment on a car or a house, the amount of the payment is a constant, but different fractions of this payment represent repayment of the principal and the interest. Also, the fraction allocated to each changes over the loan period. Using the terminology below, develop expressions for the principal and interest payments during year y: M = amount of mortgage R = nominal interest rate p = P = monthly payment annual payment r= R/12 monthly interest rate principal paid during year y interest paid during year y n = no. month for loan. X = principal paid at end of 1st month Py Iy = = 7. When we make monthly payment on a car or a house, the amount of the payment is a constant, but different fractions of this payment represent repayment of the principal and the interest. Also, the fraction allocated to each changes over the loan period. Using the terminology below, develop expressions for the principal and interest payments during year y: M = amount of mortgage R = nominal interest rate p = P = monthly payment annual payment r= R/12 monthly interest rate principal paid during year y interest paid during year y n = no. month for loan. X = principal paid at end of 1st month Py Iy = =