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For younger learners

  • Early Years Foundation Stage

Which Face?

Age 14 to 16
ShortChallenge Level Yellow star
Secondary curriculum
  • Problem
  • Solutions

Folding up the net
Imagine folding the net into a cube, starting with the face , and continuing until it reaches the top.
    

So the face  is at the bottom when the face  is at the top.


Considering edges
 
Imagine the top and the base of a cube. The top shares a (green) edge with each side that isn't the base. The base shares a (blue) edge with each of these sides. These sides only share one edge with each other.


Some of the green and blue edges are shown on the net to the right. It is enough to see that when the face  is on the top, the face  is at the bottom.



 
You can find more short problems, arranged by curriculum topic, in our short problems collection.

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Hamiltonian Cube

Weekly Problem 36 - 2007
Find the length along the shortest path passing through certain points on the cube.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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