Consider the cube shown (assume for argument's sake that it's a perfect cube, contraty to what the picture may look like).
A fly, sitting in the vertex (A) of this cube must travel the surface of the cube until it arrives at the vertex (G).
If the fly cannot leave the surface of the cube, what is the shortest path for the fly to take between the two points?
looks a pretty old puzzle posted here.
I unfolded the cude in a way it resulted in a rectangle AFGB. Then i guess AG, teh diagonal of the rectangle is the shortest distance the fly shud take to reach G from A
sqrt(5)a?