problem
Classifying solids using angle deficiency
Toni Beardon has chosen this article introducing a rich area for
practical exploration and discovery in 3D geometry
There are 27 small cubes in a 3 x 3 x 3 cube, 54 faces being visible at any one time. Is it possible to reorganise these cubes so that by dipping the large cube into a pot of paint three times you can colour every face of all of the smaller cubes?