Chapter 7 - Section 7.5 - Rationalizing Denominators and Numerators of Radical Expressions - Exercise Set - Page 445: 61

$\dfrac{5y}{\sqrt[3]{100xy}}$

Rationalizing the numerator of $ \dfrac{\sqrt[3]{5y^2}}{\sqrt[3]{4x}} $ results to \begin{array}{l} \dfrac{\sqrt[3]{5y^2}}{\sqrt[3]{4x}} \cdot \dfrac{\sqrt[3]{25y}}{\sqrt[3]{25y}} \\\\= \dfrac{\sqrt[3]{125y^3}}{\sqrt[3]{100xy}} \\\\= \dfrac{5y}{\sqrt[3]{100xy}} .\end{array}