High School

If [tex]f(3) = 191.5[/tex] when [tex]r = 0.03[/tex] for the function [tex]f(\ell) = PE^{\prime}[/tex], then what is the approximate value of [tex]P[/tex]?

A. 78
B. 175
C. 210
D. 471

Answer :

To solve this problem, we're examining the function [tex]\( f(\ell) = P \cdot E^{r\ell} \)[/tex] and given the values [tex]\( f(3) = 191.5 \)[/tex] and [tex]\( r = 0.03 \)[/tex]. We need to find the value of [tex]\( P \)[/tex].

Here's how you can approach the problem step-by-step:

1. Identify the Given Information:
- [tex]\( f(3) = 191.5 \)[/tex]
- [tex]\( r = 0.03 \)[/tex]
- We need to find [tex]\( P \)[/tex].

2. Understand the Function:
The function is given as [tex]\( f(\ell) = P \cdot E^{r\ell} \)[/tex].

3. Substitute the Given Values into the Function:
Since we know [tex]\( f(3) = 191.5 \)[/tex], [tex]\( r = 0.03 \)[/tex], and we are to find [tex]\( P \)[/tex], plug these into the equation:
[tex]\[
191.5 = P \cdot E^{0.03 \times 3}
\][/tex]
Simplifies to:
[tex]\[
191.5 = P \cdot E^{0.09}
\][/tex]

4. Calculate [tex]\( E^{0.09} \)[/tex]:
This step involves calculating the value of the exponential term [tex]\( E^{0.09} \)[/tex]. Using the numerical approximation provided:
[tex]\[
E^{0.09} \approx 1.09417
\][/tex]

5. Solve for [tex]\( P \)[/tex]:
Rearrange the equation to solve for [tex]\( P \)[/tex]:
[tex]\[
P = \frac{191.5}{1.09417}
\][/tex]

6. Calculate [tex]\( P \)[/tex]:
Perform the division to find the value of [tex]\( P \)[/tex]:
[tex]\[
P \approx 175.02
\][/tex]

7. Choose the Closest Answer:
Looking at the options given:
- A. 78
- B. 175
- C. 210
- D. 471

The approximate value of [tex]\( P \)[/tex] is 175 which matches option B.

Therefore, the approximate value of [tex]\( P \)[/tex] is 175, corresponding to option B.