Answer:
- 60-month financing period: Monthly payment = $608.29 = 608 dollars 29 cents
- 72-month financing period: Monthly payment = $526.00 = 526 dollars
Step-by-step explanation:
As she has already made the down payment of 25% (= $10,000), the principal amount of the loan is now $30,000.
The monthly payment is calculated such that at the end of the financing period (60/72 months), the principal amount must equal to 0. As such calculations are complicated and prone to errors if done manually, please see the attached Excel working file for the detailed calculations.