\begin{align}
20 \text{ years at } 2\% & \rightarrow 16.251 \text{ per } \$ 1\\
\therefore 16.351 \times 1000&=\$ 16351\\
30 \text{ years at } 2\% & \rightarrow 22.396 \text{ per } \$ 1\\
\therefore 22.396 \times 3000&=\$ 67188\\
20 \text{ years at } 2\% & \rightarrow 16.251 \text{ per } \$ 1\\
\therefore 16.351 \times 3000&=\$ 49053\\
\text{Total }&=16351+(67188-49053)\\
&=\$ 34486
\end{align}
