Question

after 5 years of earning at an annual rate of 4 percent, an investment has earned 1200 in interest. determine the amount of the initial investement

Answer 1

$\bf ~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\to &\ 1200\\ P=\textit{original amount deposited}\\ r=rate\to 4\%\to \frac{4}{100}\to &0.04\\ t=years\to &5 \end{cases} \\\\\\ 1200=P(0.04)(5)\implies \cfrac{1200}{(0.04)(5)}=P\implies 6000=P$