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Master Minding

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Flippin' Discs

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Cosy Corner

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

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?

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