You want to purchase a car, and a bank is willing to lend you $15,000. The loan will be fully amortized over 5 years (60 months), with a nominal interest rate of 12%, and interest paid monthly. a) What is the monthly loan payment? b) What is the loan's EAR (Effective Annual Rate)?
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a) To calculate the monthly loan payment of an amortizing loan, we can use the formula for a fixed installment loan which is derived from the annuity formula:
\[ P = \frac{L \times i}{1 - (1 + i)^{-n}} \]
Where: - P is the monthly payment - L is the loan amount ($15,000 in this case) - i is the monthly interest rate (annual nominal rate divided by 12) - n is the total number of payments (5 years x 12 months per year)
First, we'll calculate the monthly interest rate: The nominal interest rate is 12%, so \[ i = \frac{12\%}{12} = 1\% \text { or } 0.01 \text { per month} \]
Next, we'll calculate the number of payments: \[ n = 5 \text{ years} \times 12 \text{ months/year} = 60 \text{ payments} \]
Now, we can calculate the monthly payment (P): \[ P = \frac{$15,000 \times 0.01}{1 - (1 + 0.01)^{-60}} \] \[ P = \frac{150}{1 - (1.01)^{-60}} \] \[ P = \frac{150}{1 - (1.01)^{-60}} \] \[ P = \frac{150}{1 - 0.54792} \] \[ P = \frac{150}{0.45208} \] \[ P \approx 331.67 \]
So, the monthly payment would be approximately $331.67.
b) The Effective Annual Rate (EAR) can be calculated using the formula:
\[ (1 + i)^n - 1 \]
Where: - i is the monthly interest rate (which we've calculated as 0.01) - n is the number of periods in a year (which is 12 for monthly payments)
\[ EAR = (1 + 0.01)^{12} - 1 \] \[ EAR = (1.01)^{12} - 1 \] \[ EAR \approx 1.126825 - 1 \] \[ EAR \approx 0.126825 \text{ or } 12.6825\% \]
The loan's EAR is approximately 12.6825%.