10. As shown in the figure, on the same straight line, $A B=4 B C=3 C D=2 D E . \triangle M A C$ and $\triangle N B C$ have a combined area of 51, $\triangle M C D$ and $\triangle N C E$ have a combined area of 32, the combined area of $\triangle M C D$ and $\triangle N B C$ is
\begin{tabular}{l}
10 \\
\hline 18
\end{tabular}