Answer
$\frac{g^{7}}{15f^{4}}$
Work Step by Step
$(3375f^{12}g^{-21})^{-\frac{1}{3}}$
=$(15^{3}\times f^{12}\times g^{-21})^{-\frac{1}{3}}$
=$(15^{3})^{-\frac{1}{3}}\times(f^{12})^{-\frac{1}{3}}\times(g^{-21})^{-\frac{1}{3}}$
=$15^{-1}\times f^{-4}\times g^{7}$
=$\frac{1}{15}\times \frac{1}{f^{4}}\times g^{7}$
=$\frac{g^{7}}{15f^{4}}$
