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How many different triangles can you draw on the dotty grid which each have one dot in the middle?
The computer has made a rectangle and will tell you the number of spots it uses in total. Can you find out where the rectangle is?
Have you ever noticed the patterns in car wheel trims? These questions will make you look at car wheels in a different way!
Use your mouse to move the red and green parts of this disc. Can you make images which show the turnings described?