Cars arrive at a single bay car wash on the average of 6 per hour according to the Poisson distribution. The wash time averages 4 minutes with a standard deviation of 1 minute, but the wash time is not defined by any distribution. What is the average number of cars in line?

Arrival Rate (λ)	6.00
Service Rate (µ)	15.00 (60/4)
Standard deviation (σ)	1.00
Avg number of customers in the waiting line (Lq)=