A3 inch cube is painted on all sides with red. the cube is then cut into small cubes of dimension 1 inch. all the cubes are collected and thrown on a flat surface. what is the probability that all the top facing surfaces have red paint on them

Once again the answer is 0. The reason is because the cube is 3 by 3 there is a cube 1 by 1 in the center of the big cube, because it is surrounded by other 1 by 1 cubes that cube doesn't get any sides painted. Therefor there is no possibility for all cubes to have at least one side painted.