An understanding of probability is important in medicine, law and wider society. These problems invite students to consider some scenarios where interpreting probabilities incorrectly can have serious consequences.

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### Spots and Measles

99% of people who have measles have spots. Ben has spots. Do you think he has measles?

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### Do Rare Events Happen?

I'd be very surprised if I had three children all with the same birthday, but I read in the paper that it happened to one family...

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### The ELISA Test

In 1% of cases, an HIV test gives a positive result for someone who is HIV negative. How likely is it that someone who tests positive has HIV?

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### Matching Criminals

DNA profiling is an invaluable tool for the police. However, when it comes to probability, things aren't always as straightforward as they seem.

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### Great Expectations: Probability through problems

Articles and resources to support an intuitive approach to teaching probability.