Place four pebbles on the sand in the form of a square. Keep adding as few pebbles as necessary to double the area. How many extra pebbles are added each time?
Investigate how this pattern of squares continues. You could
measure lengths, areas and angles.
What is the area of the quadrilateral APOQ? Working on the building
blocks will give you some insights that may help you to work it
This problem is taken from the UKMT Mathematical Challenges.