I don't mean to be picky, but your formula doesn't solve the question exactly (your word). The poisson distribution is an approximation. In this problem the difference is as follows:
using # of hands = 28710 and prob of 4 deuces = 1/4900
exact answer using binomial distribution
(1-1/4900)^28710 = 0.28518...%
approx answer using poisson
(1/e)^(28710/4900) = 0.28535...%
Again, I mean no offense but when you said exactly I just wanted to point out that the poisson is an approximation. As we see, it is a very accurate one!
--- In vpFREE@yahoogroups.com, "drwusa" <drwusa@...> wrote:
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> ??? FWIW
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> here is the complete equation for solving this problem exactly
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> (1/e)^6= 0.25% where e = 2.718 (natural log)
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> --- In vpFREE@yahoogroups.com, "bogus" <boguslumber@> wrote:
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> > The spreadsheet just looks complicated in xml format. It is a very simple spreadsheet and more importantly, people can see why and how it works. Most online calculators just give you an answer and you have no idea how or why it works. In excel you can look at each formula and figure out what is happening.
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