



 
Hi Mhiko, I assume by hidden faces you mean something like this: I've highlighted the hidden faces in red. Think about the following pattern: 1 cube has no hidden faces 2 cubes has 1 hidden face 3 cubes has 2 hidden faces 4 cubes has 3 hidden faces How many hidden faces will 5 cubes have? What's the relationship between the number of cubes and the number of hidden faces? Hope this helps, Janice  


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