Answer
$\frac{12r^3}{5}$
Work Step by Step
Given.
$\frac{8r^3}{6r}\div\frac{5r^2}{9r^3}$
Simplify each rational expression.
$=\frac{4r^2}{3}\div\frac{5}{9r}$
Use the rule $\frac{a}{b}\div\frac{c}{d}=\frac{a}{b}\times\frac{d}{c}$.
$=\frac{4r}{3}\times\frac{9r}{5}$
Cancel out the common factor 3.
$=4r^2\times\frac{3r}{5}$
Multiply.
$=\frac{12r^3}{5}$