Suppose Ariana borrows [tex]$\$ 21,500$[/tex] for seven years at [tex]5.5\%[/tex] interest for the purchase of a car. Determine the monthly payment required to repay the loan and the total interest paid over the life of the loan. Round solutions to the nearest cent, if necessary.

The monthly payment is [tex]\$\square[/tex].

The total interest paid is [tex]\$\square[/tex].

Hint: Related Formula
The loan payment formula for fixed installment loans is given by the expression
[tex]
PMT = \frac{P\left(\frac{r}{n}\right)}{\left[1 - \left(1 + \frac{r}{n}\right)^{-nt}\right]}
[/tex]
where PMT is the periodic payment required to repay a loan of [tex]P[/tex] dollars, paid [tex]n[/tex] times per year over [tex]t[/tex] years, at an annual interest rate of [tex]r\%[/tex].



Answer :

To determine the monthly payment and total interest paid on a car loan of \[tex]$21,500 for seven years at an interest rate of 5.5% per year, let's follow the steps below. ### Step-by-Step Solution 1. Identify the given values: - Principal loan amount, \( P = \$[/tex]21,500 \)
- Annual interest rate, [tex]\( r = 5.5\% = 0.055 \)[/tex]
- Loan term, [tex]\( t = 7 \)[/tex] years
- Number of payments per year, [tex]\( n = 12 \)[/tex]

2. Convert annual interest rate to a monthly interest rate:
[tex]\[ \text{monthly interest rate} = \frac{r}{n} = \frac{0.055}{12} \][/tex]
[tex]\[ \text{monthly interest rate} = 0.00458333 \ (\text{approximately}) \][/tex]

3. Calculate the total number of monthly payments:
[tex]\[ \text{total payments} = n \times t = 12 \times 7 = 84 \][/tex]

4. Apply the loan payment formula:
The loan payment (PMT) formula is:
[tex]\[ PMT = \frac{P \left( \frac{r}{n} \right)}{1 - \left(1 + \frac{r}{n}\right)^{-nt}} \][/tex]
Substituting the values into the formula:
[tex]\[ PMT = \frac{21,500 \times 0.00458333}{1 - \left(1 + 0.00458333\right)^{-84}} \][/tex]

5. Calculate the numerator:
[tex]\[ \text{numerator} = 21,500 \times 0.00458333 = 98.541495 \][/tex]

6. Calculate the denominator:
[tex]\[ 1 - \left(1 + 0.00458333\right)^{-84} \][/tex]
[tex]\[ 1 - \left(1.00458333\right)^{-84} \][/tex]
[tex]\[ 1 - 0.67556 \ (\text{approximately}) \][/tex]
[tex]\[ \text{denominator} = 0.32444 \][/tex]

7. Calculate the monthly payment:
[tex]\[ PMT = \frac{98.541495}{0.32444} = 303.592 \][/tex]
[tex]\[ PMT \approx 303.59 \ (\text{when rounded to the nearest cent}) \][/tex]

8. Calculate the total payment amount over the life of the loan:
[tex]\[ \text{total payment amount} = PMT \times \text{total payments} = 303.59 \times 84 \][/tex]
[tex]\[ \text{total payment amount} = 25,501.56 \ (\text{when rounded to the nearest cent}) \][/tex]

9. Determine the total interest paid:
[tex]\[ \text{total interest paid} = \text{total payment amount} - P = 25,501.56 - 21,500 \][/tex]
[tex]\[ \text{total interest paid} = 4,001.56 \ (\text{when rounded to the nearest cent}) \][/tex]

### Final Answers:
- The monthly payment is \[tex]$308.96. - The total interest paid is \$[/tex]4452.30.

So, the monthly payment is \[tex]$308.96, and the total interest paid over the life of the loan is \$[/tex]4452.30.