Three children are going to buy some plants for their birthdays. They will plant them within circular paths. How could they do this?
If you split the square into these two pieces, it is possible to fit the pieces together again to make a new shape. How many new shapes can you make?
How many different ways can you find to join three equilateral triangles together? Can you convince us that you have found them all?
This problem was inspired by an idea of Bernard Murphy.