Answer
$3$
Work Step by Step
To solve the item mentally, note that:
$\dfrac{\sqrt[3]{15}}{\sqrt[3]{5}}=\sqrt[3]{3}$ (because of the quotient rule for radicals)
Thus, the given expression is equivalent to:
$=\sqrt[3]{3} \cdot \sqrt[3]{9}$
$\\=\sqrt[3]{27}$ (because of the product rule for radicals)
Since $27=3^3$, then
$\sqrt[3]{27}=\sqrt[3]{3^3} = 3$
Thus, the given expression is equal to $3$.