A wooden cube measuring 3 inches on each edge is painted completely red on all six faces. It is then cut into 27 identical 1-inch cubes. How many of these smaller cubes have paint on exactly two faces?
12
Cubes with paint on exactly two faces lie along the edges of the original cube, excluding the 8 corners. A cube has 12 edges, and along each 3-inch edge, exactly 1 cube sits strictly between the corners, giving 12 × 1 = 12 cubes.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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