\[\frac{x^{3} \cdot x^{22}}{\left( - x^{2} \right)^{15}} = \frac{x^{25}}{- x^{30}} = - \frac{1}{x^{5}};\]
\[x = \frac{1}{2}:\]
\[- 1\ :\left( \frac{1}{2} \right)^{5} = - 1\ :\frac{1}{32} =\]
\[= - 1 \cdot 32 = - 32.\]