Shakira buys a second-hand car for $5000. She pays a $2000 cash deposit and borrows the balance from her parents. She agrees to pay her parents $100 each month for 3 years.
a. Calculate the total amount Shakira pays to her parents.
b. How much interest does she pay?
c. Find the annual flat rate of interest charged by Shakira’s parents.

a. Repayments = 100 × 36
= $3600

b. Total paid for the car = 2000 + 3600
= $5600
Interest = $5600 – $5000 = $600

c. Interest rate = ^interest/_loan × 100
= ⁶⁰⁰/₃₀₀₀ × 100 = 20%

20% for 3 years
20 ÷ 3 = 6²/₃% pa