A Mathematical Mystery

The circumference of a circle is about three and a seventh times as long as its diameter. To be more exact, it’s 3.1416 times as long - a number called pi. 

 

For some strange reason, you get the same number if you throw a stick at some paving stones!

 

Here’s what to do: Find a place where some slabs have been laid so the cracks between them make long straight lines. (You only need to have long straight lines in one direction, not in two.)

 

If you can’t find a suitable paved area look for a large tiled floor. (Schools often have them.)

 

Remember: All you need is a set of straight lines, spaced equally. You could even use a chess board, though it’s more fun if you have something bigger.

 

If all else fails, you can draw your own set of lines on a playground or somewhere similar.

 

Now get a stick and make sure the length is exactly the same as the distance between your lines.

 

Throw the stick onto the set of lines, and notice whether it lands on a line or in between.

 

You’ll have to do this dozens of times, scoring your ‘Hits’ and ‘Misses’ on a piece of paper.

 

About 100 throws should be enough. (The number isn’t important, but the more times you do it the better it is.)

 

Once you’ve finished, add up all the hits and misses. Now use your brain or a calculator or do a sum and find the answer to the following question:

 

                                         hits divided by misses = ? 

 

You’ll probably finish up with pi. (Don’t expect to be exact: if your answer comes between 3 and 3.3 it’s good.)

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If you've done all this to find the distance round the wizard's 10 foot wheel you now know the answer: it's ten times three-and-a-bit - about 31 or 32 feet. 

 

Here's the really interesting question! Your lines were straight and your stick was straight, so how have you found pi - a number that’s specially connected with circles?

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