Question

andy deposited $1567.12 in a savings account that earns 1.9% simple interest. what will andy's account balance be in nine months?

Answer 1

Bearing in mind that,  "t" is in years, thus, since there are 12 months in a year, then 9 months is 9/12 of a year.

$\bf \qquad \textit{Simple Interest Earned Amount}\\\\ A=P(1+rt)\qquad \begin{cases} A=\textit{accumulated amount}\\ P=\textit{original amount deposited}\to& \ 1567.12\\ r=rate\to 1.9\%\to \frac{1.9}{100}\to &0.019\\ t=years\to \frac{9}{12}\to &\frac{3}{4} \end{cases} \\\\\\ A=1567.12\left( 1+0.019\cdot \frac{3}{4} \right)$