Stage: 2 Challenge Level: 
Why do this problem?
This
activity can be used as a nice straightforward introduction to
probability.
Possible approach
This can be done practically with a large group with a box
containing items to represent those in the challenge.
Key questions
Why have you decided on this?
Possible extension
Change the figures and suggest variations, for example when
items are taken out they could then be replaced before the next
selection.
Dice. Conditional probability. Theoretical probability. Equally likely outcomes. Experimental probability. Combining probabilities. Interactivities. Working systematically. Probability. Tree diagrams.
Published October 2001.
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