Question 930584
avg = 6 per hour
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POISSON Distribution
P(x = 3) = poissonpdf(6,3)= .0892
P(x ≤ 3) = poissoncdf(6,3)= .1512
Using a TI calculator 0r similarly a Casio fx-115 ES plus
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Recommend Using stattrek.com to check  Results
until You are familiar with Using Your Calculator.