Consider an espresso stand with a single barista.Customers arrive to the stand at the rate of 28 per hour according to a Poisson distribution.Service times are exponentially distributed with a service rate of 35 customers per hour.The average number of customers in the system i.e. ,waiting and being served)is
A)4.0
B)3.8
C)3.2
D)2.0

Question

Quizplus · Accepted Answer

The average number of customers in the system is given by the formula L = λ / (μ - λ), where λ is the arrival rate and μ is the service rate. In this case, λ = 28 customers per hour and μ = 35 customers per hour, so L = 28 / (35 - 28) = 4.0 customers.

Consider an Espresso Stand with a Single Barista