The left and right faces of this cube are red, the front and back blue, the top and bottom green. After it is cut into small cubes along the lines, how many show red but no blue?

Red cubes lie in the left or right slice, 16 cubes each. Of each slice, the cubes in the front and back rows also show blue: 4 + 4 = 8. That leaves 8 per slice with red but no blue, so $2\times 8=16$. (32 counts every cube that shows red.)