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## 'Two's Company' printed from http://nrich.maths.org/

A container holds $4$ yellow balls, $2$ blue balls and $1$ red
ball.

The balls are identical in all ways except colour.

Shake the container, and look at how the balls settle.

You win if two blue balls
touch.
Did you win?

Complete several shakes and look at your results.

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Approximately how often do you think you would win if you completed
$100$ throws?

Make a prediction and then check it by doing the experiment.

Can you explain how to work out the
theoretical probability of winning?

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