\[x^{2} + 27x + m = 0\]
\[\ x_{1}\ :x_{2} = 4\ :5 \Longrightarrow x_{1} = \frac{4}{5}x_{2}.\]
\[\left\{ \begin{matrix} x_{1} + x_{2} = - 27 \\ x_{1} \cdot x_{2} = m\ \ \ \ \ \ \\ \end{matrix} \right.\ \]
\[\frac{4}{5}x_{2} + x_{2} = - 27\]
\[- \frac{9}{5}x_{2} = - 27\]
\[x_{2} = - 27 \cdot \frac{5}{9}\]
\[x_{2} = - 15.\]
\[x_{1} = \frac{4}{5} \cdot ( - 15)\]
\[x_{1} = - 12\]
\[- 12 \cdot ( - 15) = m \Longrightarrow \ \ m = 180.\]
\[{Ответ:\ \ x}_{1} = - 12;\ x_{2} = - 15;\ \ \]
\[m = 180.\]