Question

Pls help (this is for a frend)

Answer 1

`~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill & \$5\\ P=\textit{original amount deposited}\\ r=rate\to 1.25\%\to (1.25)/(100)\dotfill &0.0125\\ t=years\dotfill &(1)/(2) \end{cases} \\\\\\ 5 = (P)(0.0125)((1)/(2))\implies \cfrac{5}{(0.0125)((1)/(2))}=P\implies 800=P`