Final answer:
Roberta's monthly payment on her $80,000 house loan with an APR of 7.75% is approximately $635.08.
Step-by-step explanation:
To calculate Roberta's monthly payment, we can use the formula for the monthly payment on a fixed-rate loan:
Monthly Payment = P * r * (1 + r)^n / ((1 + r)^n - 1)
Where:
- P is the principal (loan amount)
- r is the monthly interest rate (APR / 12)
- n is the total number of payments (years * 12)
Substituting in the given values:
- P = $80,000
- r = 7.75% / 12 = 0.0646
- n = 20 * 12 = 240
We can now calculate the monthly payment:
Monthly Payment = $80,000 * 0.0646 * (1 + 0.0646)^240 / ((1 + 0.0646)^240 - 1)
Using a calculator, the monthly payment comes out to be approximately $635.08.