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The Birthday Bet
Age 14 to 16
Challenge Level 
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 ?
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 ?
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