Investing Money

The final value here is given by

$${\mathtt{finalvalue}} = {\mathtt{6\,000}}{\mathtt{\,\times\,}}{\left({\mathtt{1}}{\mathtt{\,\small\textbf+\,}}{\mathtt{0.09}}\right)}^{{\mathtt{4}}} \Rightarrow {\mathtt{finalvalue}} = {\mathtt{8\,469.489\: \!66}}$$

So final value = $8469.49

So the interest earned is 

$${\mathtt{8\,469.49}}{\mathtt{\,-\,}}{\mathtt{6\,000}} = {\mathtt{2\,469.49}}$$  dollars

Thanks