Stage: 5 Challenge Level: 
You can try an experiment to test this method but you will need to repeat the trials many times to reach any convincing conclusion. This would be a good class project.
A tree diagram will help you to analyse what happens. Try calculating the probabilities for 2, 3, 4, 5 and 6 ... tosses and see if you can identify a pattern emerging.
You could try to calculate the final probabilities. Theoretically the coin tossing can go on for ever so you will need to know a bit about summing an infinite series.
Combining probabilities. Geometric sequence. Tree diagrams. Summation of series. Stage 5 - Reviewed 2012. Conditional probability. Making and proving conjectures. Spreadsheets. Experimental probability. Theoretical probability.
Published July 2009,August 2009.
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