Re: Necco Odds
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Say the first 4 wafers are the same. Does this count twice? If you get 5 in a row, does it count 3 times? You're counting them obviously. Odds change if you say 3 and only 3.
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Hi. arbuthnot was kind enough to post my crazy question here.
I want to know what the odds are of ANY three-wafer set of the same flavor showing up.
I think I have it right. If you have a roll of 40 all-chocolate Necco wafers, after all, you have 38 sets of three chocolate wafers. Right?
The problem is that if wafer 1 is not chocolate, you only lose the first possible trio (wafers 1/2/3). Same w/wafer 40 (38/39/40). But if wafer 2 or wafer 39 is not chocolate, you lose two possibilities per wafer (1/2/3, 2/3/4 and 37/38/39, 38/39/40).
Any other wafer, from 3 through 38, you lose three possible sets per nonchocolate wafer.
This makes me think there is a subtlety to this that I haven't taken into account.
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