Start with 27 small cubes. Now put them together to make one larger cube. Without touching the sides of the larger cube, remove the cube in the middle to leave 26.
(Note: No one may touch the outer cubes or in any way do anything that would move or change them)
(In reply to
the middle cube by Tristan)
well... the problem didn't say that the 'middle top' must remain in position... if the center cube melts away (and all the other cubes are porous, or allow water to go between/through them), then I suppose this would be an answer to the problem.... letting the 'top middle' slide down to the center of the 3x3x3 cube.
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What I meant to say earlier (to answer your question), was you have 13 cubes on the left side of the table (in a jumble), and 5 cubes plus a 2x2x2 'larger cube' on the right side of the table, and 1 little cube in the center (in the middle of the 27 cubes) of the table... 13 + 5 + 8 + 1 = 27 cubes.
Now, take the "middle" cube away, and you have 26 cubes remaining on the table.
(As I said... I know I'm reaching)