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# Poisson Distribution

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1. Question: "X~Po(λ) and P(X = 6) = 2 * P(X = 5). Find the value of λ."

The answer is as follows: P(X = 6) = λ/6 * P(X = 5) so λ/6 = 2 and λ = 12.

Could anyone explain how this works, where λ/6 = 2 came from?
2. For a Poisson distribution,

Sub in the values for P(X=6) and P(X=5), P(X=6) = 2P(X=5) and solve from there.
3. Ahh, yes, just remembered about the rule P(X = k + 1) = λ/(k + 1) * P(X = k), so λ/6 would have to equal 2, thank you

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