[tex]\bf \qquad \qquad \textit{Future Value of an ordinary annuity}
\\\\
A=pymnt\left[ \cfrac{\left( 1+\frac{r}{n} \right)^{nt}-1}{\frac{r}{n}} \right][/tex]
[tex]\bf \qquad
\begin{cases}
A=
\begin{array}{llll}
\textit{ amount}\\
\textit{already compounded}
\end{array}\to &
\begin{array}{llll}
1000
\end{array}\\
pymnt=\textit{periodic payments}\to &p\\
r=rate\to 4\%\to \frac{4}{100}\to &0.04\\
n=
\begin{array}{llll}
\textit{times it compounds per year}\\
\textit{quarterly, means 4 times}
\end{array}\to &4\\
t=years\to &4
\end{cases}[/tex]
solve for "pymnt"
