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A million people are signed up? How long do you have to wait on average to win a one in a million daily lottery.



Assuming people can "win" more than once and no one else signs up, the expected wait would be 1 million days.

Edit: Guess I need to explain the math since I've been downvoted.

Let X be the random variable representing the number of draws until you are the winner. The probability that X = k is (999999/1000000)^(k-1) * (1/1000000)

From the definition of expected value: E = Sum(n*P(X=n), n, 1, Infinity)

From here it's a simple matter of arithmetic to calculate E. Here's the Wolfram Alpha link since I don't feel like typing up math in this input box (shortened so as not to overflow the layout): http://bit.ly/HzRUUt


True, but the median wait time would be merely 693147 days, or around 1900 years.

1-(999999/1000000)(693147) = 0.5


Half a million days?


I'm about 50/50 sure you're correct.


Depends on how many times you register.


Depends on how many times everybody register :)




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