Given:
Unit base price: $435
Credit Card interest rate, i = 9.4% compounded monthly; i = 0.00783/month comp monthly
n = 1.5 years = 18 months
sales tax = 8.51%
First, determine the actual price of the unit by adding the sales tax to the base price of the unit:
$435 * (1 + 0.0851)
Actual price = $472.0185
So, the total amount paid by Brian should be higher than the actual price since he used his credit card. Use the formula from economics:
F = P (1+i)^n
F = $507.96
Therefore, the total amount paid by Brian is $507.96.
