Simplifying the fraction under the radical results in $\displaystyle{\sqrt[{{3}}]{{\frac{{{54}{{x}}^{{{7}-{1}}}{{y}}^{{{17}-{3}}}}}{{{125}{{z}}^{{{16}-{10}}}}}}}}={\sqrt[{{3}}]{{\frac{{{54}{{x}}^{{6}}{{y}}^{{14}}}}{{{125}{{z}}^{{6}}}}}}}\usepackage{cmbright}\Huge\$ . Pulling out third powers results in the simplified expression $\displaystyle\frac{{{3}{{x}}^{{2}}{{y}}^{{4}}}}{{{5}{{z}}^{{2}}}}{\sqrt[{{3}}]{{{2}{{y}}^{{2}}}}}\usepackage{cmbright}\Huge\$ .