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.
Can you work out the area of the inner square and give an explanation of how you did it?
$M$ is the midpoint of the side of the rectangle. What is the area (in square units) of the triangle $PMR$?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.