Answer
$\frac{81}{16}$
Work Step by Step
$(\frac{2}{3})^{-4}=\frac{1}{(\frac{2}{3})^{4}}=\frac{1}{\frac{2}{3}\times\frac{2}{3}\times\frac{2}{3}\times\frac{2}{3}}=\frac{1}{\frac{2\times2\times2\times2}{3\times3\times3\times3}}=\frac{1}{\frac{16}{81}}=\frac{81}{16}$