Final answer:
To calculate the total interest paid on a $280,000 house with a 4.1% APR over 30 years, we need the monthly payment amount. Without it, we cannot provide an exact figure, but Brad can calculate the interest by multiplying the monthly payment by 360 and subtracting the principal, which is not given in the question.
Step-by-step explanation:
When Brad finances a house with a mortgage, he will be paying both the principal and interest over the life of the loan. To calculate the total interest Brad will pay on a $280,000 house with an APR of 4.1% over 30 years, we would typically use an amortization formula or calculator. However, since we don't have the monthly payment amount or the exact formula provided in the question, we can't provide an exact figure.
An example with different numbers is given where a $300,000 loan at a different interest rate leads to paying a total of $573,847.99 over 30 years. In this case, interest and principal are both included in the total payment. Therefore, if Brad knows his monthly payment, he can multiply that by 360 (the number of months in 30 years) and subtract the original loan amount ($280,000) to find the total amount of interest paid over the course of the loan.