Evaluate:

$\sqrt[3]{\frac{-27}{125}}$

             
By factorisation:

$\sqrt[3]{\frac{27}{125}}=\sqrt[3]{\frac{3 \times 3 \times 3}{5 \times 5 \times 5}}$

$\therefore \sqrt[3]{\frac{-27}{125}}=\frac{-3}{5}$