To solve the problem, we will use the formula for the monthly payment on a fixed-rate mortgage, which is given by:
\[
M = P \frac{r(1 + r)^n}{(1 + r)^n - 1}
\]
where:
- \( M \) is the monthly payment,
- \( P \) is the loan principal (the amount borrowed),
- \( r \) is the monthly interest rate (annual interest rate divided by 12),
- \( n \) is the number of payments (loan term in months).
### (a) Monthly Payment for the 15-Year Mortgage
1. **Loan Amount (P)**: \( 246,000 \)
2. **Annual Interest Rate**: \( 4.8\% \) or \( 0.048 \)
3. **Monthly Interest Rate (r)**:
\[
r = \frac{0.048}{12} = 0.004
\]
4. **Loan Term (n)**: \( 15 \) years \( = 15 \times 12 = 180 \) months
Now, substituting these values into the formula:
\[
M = 246000 \frac{0.004(1 + 0.004)^{180}}{(1 + 0.004)^{180} - 1}
\]
Calculating \( (1 + 0.004)^{180} \):
\[
(1 + 0.004)^{180} \approx 1.8983
\]
Now substituting back into the formula:
\[
M = 246000 \frac{0.004 \times 1.8983}{1.8983 - 1}
\]
\[
M = 246000 \frac{0.0075932}{0.8983} \approx 246000 \times 0.008448 \approx 2087.01
\]
Thus, the monthly payment for the 15-year mortgage is:
\[
\boxed{2087.01}
\]
### (b) Monthly Payment for the 30-Year Mortgage
1. **Loan Amount (P)**: \( 246,000 \)
2. **Annual Interest Rate**: \( 4.8\% \) or \( 0.048 \)
3. **Monthly Interest Rate (r)**:
\[
r = \frac{0.048}{12} = 0.004
\]
4. **Loan Term (n)**: \( 30 \) years \( = 30 \times 12 = 360 \) months
Now, substituting these values into the formula:
\[
M = 246000 \frac{0.004(1 + 0.004)^{360}}{(1 + 0.004)^{360} - 1}
\]
Calculating \( (1 + 0.004)^{360} \):
\[
(1 + 0.004)^{360} \approx 3.8495
\]
Now substituting back into the formula:
\[
M = 246000 \frac{0.004 \times 3.8495}{3.8495 - 1}
\]
\[
M = 246000 \frac{0.015398}{2.8495} \approx 246000 \times 0.005396 \approx 1327.00
\]
Thus, the monthly payment for the 30-year mortgage is:
\[
\boxed{1327.00}
\]
### (c) Total Amount Paid Over the Life of Each Loan
1. **Total Amount Paid for 15-Year Mortgage**:
\[
\text{Total} = M \times n = 2087.01 \times 180 \approx 375660.18
\]
2. **Total Amount Paid for 30-Year Mortgage**:
\[
\text{Total} = M \times n = 1327.00 \times 360 \approx 478920.00
\]
Now, we can compare the total amounts:
- The total amount paid for the 15-year mortgage is \( 375660.18 \).
- The total amount paid for the 30-year mortgage is \( 478920.00 \).
To find the difference:
\[
\text{Difference} = 478920.00 - 375660.18 \approx 103259.82
\]
Thus, the 15-year mortgage from the credit union would have the lowest total amount to pay off, and it would be:
\[
\text{The total amount paid would be } \$ 103259.82 \text{ less than to the online lending company.}
\]
Final answers:
- Credit Union: \( \boxed{375660.18} \)
- Online Lending Company: \( \boxed{478920.00} \)
- Difference: \( \boxed{103259.82} \)
(a) Monthly payment for 15-year mortgage: \$2087.01
(b) Monthly payment for 30-year mortgage: \$1327.00
(c) Total amount paid for 15-year mortgage: \$375,660.18
(d) Total amount paid for 30-year mortgage: \$478,920.00
(e) Difference: \$103,259.82