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## 'Triangles All Around' printed from http://nrich.maths.org/

You might like to have a look at

Nine-Pin Triangles before trying this problem.

How many different triangles can you draw on a circular pegboard which has four equally spaced pegs?

What are the angles of each triangle?

If you have a six-peg circular pegboard, how many different triangles are possible now?

What are their angles?

How many different triangles could you draw on an eight-peg board?

Can you find the angles of each?

You may like to use the interactivity to try out your ideas.

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This text is usually replaced by the Flash movie.

For printable sets of circle templates for use with this activity, please see

Printable Resources page.

Many thanks to Geoff Faux who introduced us to the merits of the 9 pin circular geoboard.

For further ideas about using geoboards in the classroom, please see Geoff's publications available through the Association of Teachers of Mathematics (search for 'geoboards').