\[\frac{32m^{2}}{n^{3}} \cdot \left( \frac{n}{2m} \right)^{5} =\]
\[= \frac{32m^{2}}{n^{3}} \cdot \frac{n^{5}}{32m^{5}} = \frac{n^{2}}{m^{3}}.\]