Question

Find how much should be invested to have $8,500 in 9 months at 5.6% simple interest.

Answer 1

let's recall that a year has 12 months, so 9 months is really 9/12 of a year.

`~~~~~~ \textit{Simple Interest Earned Amount} \\\\ A=P(1+rt)\qquad \begin{cases} A=\textit{accumulated amount}\dotfill & \$ 8500\\ P=\textit{original amount deposited}\\ r=rate\to 5.6\%\to (5.6)/(100)\dotfill &0.056\\ t=years\to (9)/(12)\dotfill &(3)/(4) \end{cases} \\\\\\ 8500 = P[1+(0.056)((3)/(4))] \implies 8500=P(1.042) \\\\\\ \cfrac{8500}{1.042}=P\implies 8157.39\approx P`