The Birthday Problem
Introduction
The question: How many people need to be in a room for there to be a 50% chance that at least two people share a birthday?
How would you go about answering this? Think about it for a minute, then come back. What strategy did you use? If your thoughts were in the vein of "50% of 365 = 183" meaning we would need 183 people in a room, many other people have the same intuition as you (Frost, 2020). However, the actual number is much smaller than 183 and might surprise you, which is why this famous problem is sometimes referred to as the birthday paradox. Keep reading through the next pages to learn more about the background of this problem and the math behind why only 23 people need to be in a room for there to be a 50% chance that at least two people share a birthday!
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