Can you make the most extraordinary, the most amazing, the most
unusual patterns/designs from these triangles which are made in a
Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
A tennis ball is served from directly above the baseline (assume
the ball travels in a straight line). What is the minimum height
that the ball can be hit at to ensure it lands in the service area?
This problem is taken from the UKMT Mathematical Challenges.