In a Factory, Machines Breakdown at an Average of 6

Short Answer

In a factory, machines breakdown at an average of 6 machines per hour according to a Poisson distribution. The time a repair person takes to repair the machine is not defined by any probability distribution, but has a mean of 8 minutes and a standard deviation of 3 minutes.
-On average, how many machines are in the system either being repaired or waiting in line to be repaired?