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

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

Answer :

To solve for the approximate value of [tex]\( P \)[/tex] in the equation [tex]\( f(t) = P \cdot e^{rt} \)[/tex], we are given the following information:

- [tex]\( f(3) = 191.5 \)[/tex]
- [tex]\( r = 0.03 \)[/tex]

The function can be rewritten as:

[tex]\[ f(t) = P \cdot e^{r \cdot t} \][/tex]

We can substitute the given values [tex]\( f(3) = 191.5 \)[/tex], [tex]\( r = 0.03 \)[/tex], and [tex]\( t = 3 \)[/tex] into the equation:

[tex]\[ 191.5 = P \cdot e^{0.03 \cdot 3} \][/tex]

First, calculate the exponential part:

[tex]\[ e^{0.03 \cdot 3} = e^{0.09} \][/tex]

Now compute [tex]\( e^{0.09} \)[/tex]:

The approximate value is [tex]\( e^{0.09} \approx 1.094 \)[/tex].

Substitute this back into the equation:

[tex]\[ 191.5 = P \cdot 1.094 \][/tex]

Solve for [tex]\( P \)[/tex] by dividing both sides by 1.094:

[tex]\[ P \approx \frac{191.5}{1.094} \][/tex]

[tex]\[ P \approx 175 \][/tex]

Thus, the approximate value of [tex]\( P \)[/tex] is 175, which corresponds to option B.