The regular payment amount, rounded to the nearest dollar, is approximately $855.
How did we get the value?
The standard formula to calculate the monthly payment (PMT) for a fixed-rate mortgage is:
![\[ PMT = P * (r(1+r)^n)/((1+r)^n - 1) \]](https://img.qammunity.org/2024/formulas/mathematics/college/omifn3k7zzw9iewi9jp45om76urn55qgxb.png)
where:
-
is the principal amount (loan amount),
-
is the monthly interest rate (annual interest rate divided by 12 and expressed as a decimal),
-
is the number of payments (loan term in years multiplied by 12).
Let's calculate the monthly payment amount:
(a) Calculate the Down Payment:
![\[ \text{Down Payment} = 0.20 * \$139,000 = \$27,800 \]](https://img.qammunity.org/2024/formulas/mathematics/college/z5mmzhse4ve1j3qh30hoyn0hjlb4hcowc1.png)
(b) Calculate the Loan Amount (Principal):
![\[ \text{Loan Amount} = \$139,000 - \$27,800 = \$111,200 \]](https://img.qammunity.org/2024/formulas/mathematics/college/f2sum48rmb14c0z7ywo6x8fhpftis1efqz.png)
(c) Calculate the Loan Term in Months (n):
![\[ n = 30 * 12 = 360 \]](https://img.qammunity.org/2024/formulas/mathematics/college/ygzfysh6i6r5khhgmi7pbtgxy2nqf8xdk8.png)
(d) Calculate the Monthly Interest Rate (r):
![\[ r = (0.085)/(12) \]](https://img.qammunity.org/2024/formulas/mathematics/college/m5czkgszexivrj0swfk07juoic8ci7zy4s.png)
Let's calculate the monthly interest rate:
![\[ r = (0.085)/(12) \approx 0.0070833 \]](https://img.qammunity.org/2024/formulas/mathematics/college/l61ojvwxa8hie3qio61rdoxh93uiyfor1p.png)
(e) Use the Formula to Calculate Monthly Payment (PMT):
![\[ PMT = (\$111,200 * 0.0070833 * (1+0.0070833)^(360))/((1+0.0070833)^(360) - 1) \]](https://img.qammunity.org/2024/formulas/mathematics/college/etck8lvkco0d53ajknbqp3mrfjofg02tyi.png)
Calculating this expression will give you the monthly payment amount. Rounding to the nearest dollar, the result is:
![\[ PMT \approx \$855 \]](https://img.qammunity.org/2024/formulas/mathematics/college/l7itz73iim0z781vbyxe43qhpl0dab0zqc.png)
So, the regular payment amount, rounded to the nearest dollar, is approximately $855.