Arrivals at a fastfood restaurant follow a Poisson distribut

Arrivals at a fast-food restaurant follow a Poisson distribution with a mean arrival rate of 16 customers per hour. What is the probability that in the next hour there will be exactly 12 arrivals?

0.0000

0.0661

0.7500

0.1322

None of these

Solution

For Poisson,

P(X) = mean^x*e^-mean/x!

Mean = 16

P(x = 12) = (16^12)*(e^-16)/12! = 0.0661 (answer)