Answer
$\frac{8x^{15}y^8z}{25}$
Work Step by Step
(2x$^3$y$^4$z)$^3$$\times$(5x$^{-3}$y$^2$z)$^{-2}$
=(8x$^9$y$^{12}$z$^3$)$\times$($\frac{1}{25}$x$^6$y$^{-4}$z$^{-2}$)
$=\frac{8(x^9)(x^6)(y^{12})(z^3)}{25(y^4)(z^2)}$
$=\frac{8x^{15}y^8z}{25}$