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## 'Cosy Corner' printed from http://nrich.maths.org/

A container holds $3$ red balls, $2$ blue balls and $1$ yellow
ball.

The balls are identical in all ways except colour.

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

You win if at least one of the red
balls is in a corner.
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Did you win?

Complete several shakes and look at your results.

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

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

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

You may find
these sheets useful if you want to work on paper or submit a
solution.