Question

Suppose that on average every hour 10 customers enter a departmental store.

a. Calculate the probability that in an hour 12 customers entered the Store.

Answer 1

Solution:

$\lambda=10$

Let $X$ be the random variable denoting the number of customers per hour.

$X\sim Poisson(\lambda)$

$P(X=12)=\dfrac{e^{{-10}}({10})^{12}}{12!}=0.09478$