What is -(-1/2)^3?
$$-(\frac{-1}{2})^3\\\\ =-\frac{(-1)^3}{(2)^3}\\\\ =-\frac{-1}{8}\\\\ =\frac{1}{8}\\\\$$
the ansewer is 0.125.
It has to be in factions
$${\frac{{\mathtt{125}}}{{\mathtt{1\,000}}}}$$
or even that.