\[\frac{3x^{3}y^{2}}{8m^{2}n} \cdot \frac{16xm^{3}}{27y^{4}n^{8}} \cdot \frac{18n^{2}y^{2}}{4x^{2}m} =\]
\[= \frac{3x^{3}y^{2} \cdot 16xm^{3} \cdot 18n^{2}y^{2}}{8m^{2}n \cdot 27y^{4}n^{8} \cdot 4x²m} = \frac{x^{2}}{n^{7}}\]