Birthday Paradox

Formula and Examples for calculating the birthday paradox


The birthday paradox descript the probability that, in a set of n people, at least two will share a birthday. The birthday paradox refers to the counterintuitive fact that only 23 people are needed for that probability to exceed 50%.

Formula

Birthday formula

The following example shows the calculation for 3 people.

Birthday example

Das folgende Beispiel zeigt die Berechnung für 5 Personen.

Birthday formula

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