Sample Question #185 (probability brainteaser)

One July 4th weekend you go to Jones Beach [a large, popular public beach on Long Island, NY] and find the beach overcrowded with what seems to be one million beachgoers. You also notice that everyone is looking at someone else.

What’s the probability that, at any given moment, no one is looking at you?

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*Related*

This video clip, from Sydney, shows you how relevant the "Beach Puzzle" question is. Hmm…

-brett

HINT

(no answer yet…)

What’s the probability if there’s just one other person on the beach, two other people on the beach, three other people on the beach, etc.? You’re looking for the probability limit as the number of other people goes to infinity.

1/e?

1-(999999/1000000)^999999=1-0.36788=0.63212

Actually, I think it is (999999/1000000)^999999 = 1/e