Imagine you are suspending a cube from one vertex (corner) and
allowing it to hang freely. Now imagine you are lowering it into
water until it is exactly half submerged. What shape does the
surface of the water make around the cube?
Imagine you have six different colours of paint. You paint a cube
using a different colour for each of the six faces. How many
different cubes can be painted using the same set of six colours?
A rectangular field has two posts with a ring on top of each post.
There are two quarrelsome goats and plenty of ropes which you can
tie to their collars. How can you secure them so they can't fight
each other but can reach every corner of the field?
Here is a solution from Adam and Chris at Moorfield School:
"A square appears becase the amount of squares on the sides of
triangle are more than the sides of the trapezium. The square comes
from the triangle.
The sloping sides don't fit exactly so they give you an extra