bobbym wrote:

Hi wintersolstice;

I can't see any drawing or page. Post the problem and the diagram, if you can.

here:

http://www.mathsisfun.com/games/unfolded-cube-puzzle.html

I don't understand what the "unfolded cube" tells you about the final cube

The real 27 cubes have some blue and some clear cubes.  The left hand diagram doesn't show you what the faces are like but rather how many cubes in a given line are blue and how many are clear.

As you look at a face you might be looking at blue cube that has another blue cube behind and another blue cube behind that. The left hand view indicates this by showing a deep blue square.

Or you might be looking at a cube that is clear, with a blue behind and another blue behind that.  This is shown on the left hand view by a mid blue square.

Or you might be looking at a clear, with a clear behind with a blue behind that.  This is shown on the left hand view by a light blue square.

And so on.

So the left hand view doesn't show the outer faces; it shows whether there are three, two, one or no blue cubes in that line.  Altogether this gives 6 x 9 bits of information about which cubes are blue and which are clear.

So work this out and show what the outer faces look like on the right hand diagram.

I hope this makes sense to you.

I've just re-read it; and I'm not even sure it makes sense to me!  So I've made a revised left hand diasgram in which the numbers tell you how many blue cubes there are 'in that line'.  Hope that helps.

Bob

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Last edited by bob bundy (2010-07-29 21:57:31)