Suppose a cube is on a piece of paper. The piece of paper is exactly three times as width and in length as the cube, so that you can place the cube in the middle of the 3×3 paper like this:
Now the question is to cover the entire cube with paper. Following rules apply:
- the cube stays in the middle of the paper.
- You can cut the paper but only at the given 3×3 boundaries/ribs.
- Fold only over the boundaries/rib.
- Do not cut off (loose) any 1×1 from the 3×3. You won’t need to do so.