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a statistics professor finds that when she schedules an office hour for student help, an average of 2.4 students arrive. find the probability that in a randomly selected office hour, the number of student arrivals is 2

User Dimger
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1 Answer

4 votes

Answer:

P=0.2613

Explanation:

-Notice that this is a poison probability distribution problem.

-The Poisson probability function is expressed as:


P(X=x)=(\lambda^x e^(-\lambda))/(x!)

where:

  • x=0,1,2,3

  • e Euler's constant

  • \lambda =mean number of occurrences.

Given that x= 2 and
\lambda=2.4, the probability is calculated as:


P(X=2)=(\lambda^xe^(-\lambda))/(x!)\\\\=(2.4^2e^(-2.4))/(2!)\\\\\\=0.2613

Hence, the probability that in a randomly selected office hour, the number of student arrivals is 2 is 0.2613

User Jacek Blaszczynski
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