For the beauty contest, I you are correct that odds are 2/n for any given day. And your understanding of lottery with respect to betting on the 2 members being selected is correct also.

I had to go back and check the login page for MOTD since I usually just blow right past it. Lo and behold, there I was. :)

Care to discuss the odds in Powerball lottery??? :)

>Hi Mark,
>
>First of all, my congratulations to you as MOTD :)
>
>Second, I thought today at morning about probability and finally I understood the difference. Let's me explain:
>The probability to be one of two selected persons in beaty contest is
>2/n - this is from beaty point of view
>If you're the viewer and you bet, that beaty_k and beaty_m would win, the probability is 2/n * 1/[n-1]
>
>Now, see the difference? So, you're in or you're out???????? :)
>
>And if the beaty contest is holded each day and among the same persons, the probability to win eventually would be even more, than 1 :)
>