Question

LF Bank has 3 tellers serving customers through a shared line where the next customer in line goes to the first available teller. Each teller can serve 30 customers per hour with exponential service times and the customers arrive at a rate of 47 per hour, according to a Poisson distribution. On average, how many customers are in the system? (Note: carry all your results to at least 4 decimal places)

Round your final answer to 2 decimal places.

Answer 1

= arrival rate

= service rate per teller

s = no. of teller

P₀ = Probability that there are no customers in the system

P₀ = 1/[1/n!(/)ⁿ]+1/s!(/)^s(s/s-), n= 0 to n = s-1

L = no. of customers in the system

L =( (/)^sP₀/(s-1)!(s-)²) + (/)