### Three Cubes

Can you work out the dimensions of the three cubes?

### Nine Colours

Can you use small coloured cubes to make a 3 by 3 by 3 cube so that each face of the bigger cube contains one of each colour?

### Marbles in a Box

How many winning lines can you make in a three-dimensional version of noughts and crosses?

# Painted Cube

##### Age 14 to 16 Challenge Level:

Imagine a large cube made up from $27$ small red cubes.

Imagine dipping the large cube into a pot of yellow paint so the whole outer surface is covered, and then breaking the cube up into its small cubes.

How many of the small cubes will have yellow paint on their faces?
Will they all look the same?

Now imagine doing the same with other cubes made up from small red cubes.
What can you say about the number of small cubes with yellow paint on?