Answer
0.125
Work Step by Step
take the exponent on the other side of the fraction
$\frac{1}{4^{\frac{3}{2}}}$
As we know $a^{\frac{b}{c}}$ = $\sqrt[c] a^{b}$
So $\frac{1}{\sqrt[2] 4^{3}}$
= $\frac{1}{\sqrt 64}$
= $\frac{1}{8}$
= 0.125