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My coat has three different buttons.
Sometimes, I do them up starting with the top button. Sometimes, I start somewhere else.
How many ways can you find to do up my coat?
How will you remember them?
Do you think there are any more? How do you know?
This problem was inspired by an idea of Bernard Murphy.
Three children are going to buy some plants for their birthdays. They will plant them within circular paths. How could they do this?
How many different ways can you find to join three equilateral triangles together? Can you convince us that you have found them all?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?