math
posted by Moyer on .
Suppose a car cost 32000 and you are allowed to make a down payment of 20%, but have to borrow the remaining 80%. If you are allowed 5 years to pay back the loan, how much will you pay back monthly?

What interest rate is your lender charging you?
Without figuring interest,
32,000 * 0.8 = 25,600
25,600 / 60 = ? 
The interest rate is 3.69%

let the monthly payment be P
i = .0369/12 = .003075
n = 60
80% of 32000 = 25600
P( 1  1.003075^60)/.003075 = 25600
P = $467.89