\[\boxed{\mathbf{314}.}\]
\[\left\{ \begin{matrix} x^{5} + bx^{4} + cx^{3} = M_{1}(x)(x + 2) \\ x^{5} + bx^{4} + cx^{3} = M_{2}(x)(x - 3) \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} ( - 2)^{5} + ( - 2)^{4}b + ( - 2)^{3}c = 0 \\ 3^{5} + 3^{4}b + 3^{3}c = 0\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} - 32 + 16b - 8c = 0\ \ \ |\ :8 \\ 243 + 81b + 27c = 0\ \ |\ :9 \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} 2b - c = 4\ \ \ \\ 3b + c = - 9 \\ \end{matrix} \right.\ ( + )\]
\[5b = - 5\]
\[b = - 1.\]
\[c = 2b - 4 = - 2 - 4 = - 6.\]
\[Ответ:b = - 1;\ \ c = - 6.\]