# Math Help - Find the initial investment?

1. ## Find the initial investment?

Captinblack invested some money at 10% compounded quarterly at the end of three years his investmenthad grown to $2488.05. Find the initial investment. My answer is$1850.00 thanks for checking.

2. Greetings Kwtolley:

I have but one word to utter in response to your work here today...Perfect!

Enjoy,

Rich B.

3. Hello, kwtolley!

Captain Blackbeard invested some money at 10% compounded quarterly.
At the end of three years his investmenthad grown to $2488.05. Find the initial investment. My answer is$1850.00

I assume you used a variation of : . $A\;=\;P\left(1 + \frac{i}{n}\right)^{nt}$

Then: . $P \;=\;\frac{2488.05}{\left(1 + \frac{0.10}{4}\right)^{12}} \;=\;1850.00422 \;\approx\;\1850$

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It's hard to see your work from here . . .

It looks like you played the $J\heartsuit$ instead of the $7\clubsuit$.

Then you transposed to the key of $F\sharp\text{ minor}$ instead of $E\flat\text{ major}$.

Lucky for you, the two errors canceled out.