Having the price of the car and the interest rate and insurance rate, we can calculate the monthly payment as follows:
RYMCO Vehicle:A $20,000
Bank X rate: 4.5% ( per year)
Insurance rate: 10% ( on 5 years)
Loan period: 5 years or 60 months (Meaning 60 payments)
Down payment: 20%

Down payment = car price x Down payment rate
= $20,000x 20%
= $4,000

Interest costA A A = total price x insurance rate
=$20,000 x 10%
=$2,000

Cash to finance = car price – down payment
= $20,000- $4000
= $ 16,000

Total to finance = Cash to finance + Interest cost
= $ 16,000 + $2,000
=$ 18,000

Interest amount over 5 years =Total to finance x interest rate x 5 years
= $ 18,000 x 4.5% x 5
=$ 4,050

Monthly payment = total to finance + interest amount over 5 years / 60 payments (60 months)
A A A A A A A A A =($18,000 + $4,050) /60
A A A A A A A A A =$ 367.5

Therefore, we will have the following:
Car price : $20,000
Down payment: $4,000
Loan period: 60 months
Insurance amount: $ 2,000
Monthly payment: $ 367.5