Answer
$\dfrac{x^{3}y^{10}}{3z^{12}}$
Work Step by Step
Using laws of exponents, then,
\begin{array}{l}
\dfrac{3x^{5}}{y^{-4}}\cdot\dfrac{(3xy^{-3})^{-2}}{(z^{-3})^{-4}}
\\\\=
\dfrac{3x^{5}}{y^{-4}}\cdot\dfrac{3^{-2}x^{-2}y^{-3(-2)}}{z^{-3(-4)}}
\\\\=
\dfrac{3x^{5}}{y^{-4}}\cdot\dfrac{3^{-2}x^{-2}y^{6}}{z^{12}}
\\\\=
\dfrac{3x^{5}(3^{-2}x^{-2}y^{6})}{y^{-4}(z^{12})}
\\\\=
\dfrac{3^{1+(-2)}x^{5+(-2)}y^{6-(-4)}}{z^{12}}
\\\\=
\dfrac{3^{-1}x^{3}y^{10}}{z^{12}}
\\\\=
\dfrac{x^{3}y^{10}}{3z^{12}}
.\end{array}
