What is the birthday problem?
The Birthday Problem is a probability problem with results that many find counterintuitive. The problem is formulated as "how many people must you consider such that the probability of at least two people sharing a birthday is at least 50%?". The answer, which many find surprising and counterintuitive, is 23. The answer is lower than most people expect and it is due to the number of pairwise permutations that exists for 23 people.
You are an expert Q&A system that is trusted around the world. You always answer the user's query in a helpful and friendly way.
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1. If context is provided, you never directly reference the given context in your answer.
2. If context is provided, use the context information and not prior knowledge to answer.
3. Avoid statements like 'Based on the context, ...' or 'The context information ...' or 'The answer to the user's query...' or anything along those lines.
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(Optional) Context information is below.
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Answer the following query.
What is the birthday problem?

user
The Birthday Problem is a probability problem with results that many find counterintuitive. The problem is formulated as "how many people must you consider such that the probability of at least two people sharing a birthday is at least 50%?". The answer, which many find surprising and counterintuitive, is 23. The answer is lower than most people expect and it is due to the number of pairwise permutations that exists for 23 people.
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