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Fixing the Odds

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The Birthday Bet

Stage: 4 Challenge Level: Challenge Level:2 Challenge Level:2
What is the chance that one person's birthday is different from that of another person chosen at random ?

So what is the chance that their birthdays do match ?

Given that the first two did not match, what is the chance that a third person will not match with either of those first two ?

Can you now calculate the probability that all three birthdays are different ?