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How many people are needed so that the probability that at least one of them has the same birthday as you is greater than 12?

Short Answer

Expert verified

The probability the same birthday found to be253.

Step by step solution

01

Given Information

The probability that at least one person has the same birthday as me is greater than12.

02

Calculation

Suppose that there are npeople.

The probability that non of them has the same birthday as me is simply

364365n

03

Substitution

So the probability that at least one person has the same birthday as me is greater than 12if and only if

1-364365n≥12

⇔364365n≤12

⇔nlog364365≤log12

⇔n≥252.65.

04

Final answer

The probability that at least one person has the same birthday as me is greater than12has found to be253.

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