Calculating the interest rate I borrow R3 000 from the bank to buy a wheelchair for my sick brother. The contract stipulates that I have to repay the bank R3 900 after 2 years. a. How much interest must I pay the bank per year? b. What is the interest rate I have to pay? c. If I decide to repay the bank weekly, what will my weekly instalment be? d. If I repay the loan after one year the bank will only charge me R3 360. What will the interest rate be if I repay them after one year? ​