help please its my last one!

Using compound interest, it is found that they must deposit $9,143.47 in order to have the desired amount.
The amount of money earned, in compound interest, after t years, is given by:
[tex]A(t) = P\left(1 + \frac{r}{n}\right)^{nt}[/tex]
In which:
For this problem, the parameters are:
A(15) = 30000, r = 0.08, n = 4
Then we solve for P to find the initial deposit:
[tex]A(t) = P\left(1 + \frac{r}{n}\right)^{nt}[/tex]
[tex]30000 = P\left(1 + \frac{0.08}{4}\right)^{4 \times 15}[/tex]
[tex]P = \frac{30000}{(1.02)^{60}}[/tex]
P = $9,143.47.
More can be learned about compound interest at https://brainly.com/question/25781328
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