In calculating the monthly payment for a loan with an [tex]$8.5\%$[/tex] interest rate compounded monthly, what value should be used for [tex]$i$[/tex], the interest rate per period, as it appears in the following formula?

[tex]\[ P = PV \cdot \frac{i}{1 - (1 + i)^{-\pi}} \][/tex]

A. 8.5
B. 0.71
C. 0.085
D. 0.0071

Please select the best answer from the choices provided:
A
B
C
D



Answer :

Sure, let's solve this step by step.

1. Understanding the Problem:
- We need to find the monthly interest rate per period, denoted as [tex]\(i\)[/tex], for an annual interest rate of [tex]\(8.5\%\)[/tex].

2. Converting Annual Interest Rate to Monthly Interest Rate:
- The annual interest rate given is [tex]\(8.5\%\)[/tex].
- Interest rates are typically expressed as a percentage, so [tex]\(8.5\%\)[/tex] means [tex]\(8.5\)[/tex] per [tex]\(100\)[/tex], mathematically written as [tex]\(8.5/100\)[/tex].

3. Monthly Interest Rate:
- To convert an annual interest rate to a monthly interest rate, we need to divide by [tex]\(12\)[/tex], since there are [tex]\(12\)[/tex] months in a year.
- So, the monthly interest rate is:
[tex]\[ \text{Monthly interest rate} = \frac{8.5}{12}/100 \][/tex]
- Simplifying the division:
[tex]\[ \text{Monthly interest rate} = \frac{8.5}{1200} \][/tex]

4. Numerical Value of Monthly Interest Rate:
- Evaluating the fraction [tex]\(\frac{8.5}{1200}\)[/tex] results in approximately [tex]\(0.007083333333333334\)[/tex].

5. Selecting the Best Answer:
- Comparing this result with the choices provided,
[tex]\[ \text{Choices:} \][/tex]
- (a) [tex]\(8.5\)[/tex]
- (b) [tex]\(0.71\)[/tex]
- (c) [tex]\(0.085\)[/tex]
- (d) [tex]\(0.0071\)[/tex]

- The closest and most accurate value corresponding to our obtained result [tex]\(0.007083333333333334\)[/tex] is:
[tex]\[ d. \quad 0.0071 \][/tex]

Thus, the best answer is:
[tex]\[ \boxed{0.0071} \][/tex]