# How do you simplify (81/625)^(-1/4)?

${\left(\frac{81}{625}\right)}^{- \frac{1}{4}} = {\left(\frac{625}{81}\right)}^{\frac{1}{4}} = {\left({5}^{4} / {3}^{4}\right)}^{\frac{1}{4}} = {\left({\left(\frac{5}{3}\right)}^{4}\right)}^{\frac{1}{4}} = \frac{5}{3}$