Can any one help to solve this...its the only problem im struggling with

Question

F has borrowed R3000. After setting up a budget, R85 was the maximum monthly payment she could afford to make on the loan. calculate and print the interest, the principal, and the balance on the loan per month. Other information she would like to know is the number of years and months it will take to pay the loan back and the total interest she will pay during that period. interest rate is 1% per month on unpaid balance.
Interest=balance * interest rate
Payment=balance-payment
new balance=balance-payment

Answer 1

number if years and month can be known from number of payments and that is 3000/85 》36 months the 36 / 12 that will give 3 years u can replace those with vars like total_payment , settlement_fee , period_month, period_year that is for starting

Answer 2

then u can declare a class name i.e. loan with those vars and 3 methods interest, payment, Palance may be it will be unless there is a complex interest that will go for the delayed payment too.