\[\left( \frac{- 16x^{2}}{27y^{3}} \right)^{2} \cdot \left( \frac{9y^{2}}{8x^{2}} \right)^{3} =\]
\[= \frac{2^{8}x^{4}}{3^{6} \cdot y^{6}} \cdot \frac{3^{6}y^{6}}{2^{9}x^{6}} = \frac{1}{2x^{2}}\]