Little's law was proved by John Little in 1961. His results apply to any system and systems within a system. For example, in a bank, the customer line may be one subsystem, and each of the tellers is another subsystem, and the result can be applied to each one system as well as the whole system.
It suggests that the long term average number of customers in a system N, should be equal to the long term arrival rate λ, multiplied by the long term avg. Time that customer spends in the system T. Or in other words:N= λT
It suggests that the long term average number of customers in a system N, should be equal to the long term arrival rate λ, multiplied by the long term avg. Time that customer spends in the system T. Or in other words:N= λT
