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### Teddy Town

There are nine teddies in Teddy Town - three red, three blue and three yellow. There are also nine houses, three of each colour. Can you put them on the map of Teddy Town according to the rules?

### Four Triangles Puzzle

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# Dotty Circle

##### Stage: 2 Challenge Level:

Watch the film below.
Full Screen Version
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Please see http://nrich.maths.org/techhelp/#flash to enable it.

Try to describe what happens in the film to someone else.

Imagine the dot starts at the point (1,0), turns through $20^\circ$ and then stops:

If the point now carries on, through how many degrees must it turn to finish the same height above or below the horizontal axis as it was when it had gone through $20^\circ$?

Can you find a general rule for explaining when the dot will be this same distance from the horizontal axis?

You might like to try Round and Round and Round after this problem.

This film is based on one developed by Alf Coles - thank you to Alf for allowing us to use these ideas. You can watch all Alf's films at http://www.mathsfilms.co.uk