Trinomial Cubes

A box containing 27 cubes and cuboids to represent the formula (a b c)3 =a3 b3 c3 3ab2 3ba2 3bc2 3cb2 3ac2 3ca2 6abc .The lid is printed with the corresponding colours of red, blue, yellow and black to hep the children assemble the pieces. The material is manufactured with a high degree of precision and accuracy such that the pieces sit precisely against each other on all sides.