Question

Use the simple interest formula to find the principal invested if $790 interest was earned in 5 years at an interest rate of 4%

Answer 1

`~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill&\$790\\ P=\textit{original amount deposited}\\ r=rate\to 4\%\to (4)/(100)\dotfill &0.04\\ t=years\dotfill &5 \end{cases} \\\\\\ 790=P(0.04)(5)\implies \cfrac{790}{(0.04)(5)}=P\implies \boxed{3950=P}`