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Two's Company

Age 11 to 14 Challenge Level:

A container holds $4$ yellow marbles, $2$ blue marbles and $1$ red marble.
The marbles are identical in all ways except colour.
Run the interactivity below to simulate shaking the container.

You win if two blue marbles touch.

Did you win?
Complete several shakes and look at your results.



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 find a way of working out the theoretical probability of winning?

You may find this Recording Sheet useful.