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Rain or Shine

Predict future weather using the probability that tomorrow is wet given today is wet and the probability that tomorrow is wet given that today is dry.

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If the score is 8-8 do I have more chance of winning if the winner is the first to reach 9 points or the first to reach 10 points?

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Playing Squash

Playing squash involves lots of mathematics. This article explores the mathematics of a squash match and how a knowledge of probability could influence the choices you make.

Ante Up

Age 16 to 18 Challenge Level:

Draw a tree diagram to get started.
You could also fill in a table for all possible outputs for, say, the first 5 letters produced to get a feel for the problem and which sequences will win first. 
You can also read which has answers to the required computations.