You have a 3x3x3 cube, built with 1x1x1 bricks (27 bricks in total).

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Discussion Overview

The discussion revolves around a problem involving a 3x3x3 cube constructed from 1x1x1 bricks, specifically addressing the feasibility of reconstructing the remaining structure after removing two diagonally opposite bricks. The scope includes theoretical reasoning and mathematical exploration related to cube dimensions and brick arrangements.

Discussion Character

  • Exploratory, Debate/contested, Mathematical reasoning

Main Points Raised

  • One participant poses the question of whether the remaining structure can be built from 2x1x1 bricks after removing two diagonally opposite bricks from a 3x3x3 cube.
  • Another participant suggests that the problem is trivial for odd-dimension cubes but raises the possibility of complications for even-dimension cubes, specifically a 4x4x4 cube, depending on the interpretation of "long diagonal."
  • A later reply acknowledges the triviality of the odd-order cube but asserts that the 4x4x4 case, or any even-order cube, presents its own challenges, indicating that the solution is more complex.
  • One participant expresses uncertainty regarding the dimensional aspects of the problem, indicating a lack of confidence in their understanding of the brick arrangement challenge.

Areas of Agreement / Disagreement

Participants do not reach a consensus; there are competing views regarding the implications of cube dimensions on the problem's solvability, particularly between odd and even dimensions.

Contextual Notes

Unresolved aspects include the specific definitions of "long diagonal" and the implications of cube dimensions on the ability to reconstruct the figure, which may affect the overall understanding of the problem.

Werg22
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You have a 3x3x3 cube, built with 1x1x1 bricks (27 bricks in total). You remove two diagonally opposite bricks (long diagonals). Can you build the remaining figure from 2xx1x1 bricks?
 
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i'm going to say:
no
the shapes volume is now 25 bricks
this would take 25 1x1x1 bricks
or 12.5 2x1x1 bricks
unless your allowed to have half a 2x1x1 brick, you can't do it?
unless I've missed something
 


Yeah, this problem becomes trivial if you've got an odd-dimension cube. However, it may still be impossible if it's a 4x4x4 cube, for different reasons, which I think is what the OP was going for. Just have to imply a different meaning of "Long Diagonal"-- that is, instead, you want to remove 2 cubes diagonally opposite on the same "plane" of the cube.

DaveE
 


Dave is right, I didn't realize the triviality of an odd-order cube :redface:

Still though, like he pointed out, the 4x4x4 case, or any order for that matter, is impossible too. But the solution (at least the one I know) is much harder!
 


There is a problem in dimension with its first digit. So, i am not guessing answer about this bricks game.
 

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