4.2. Little’s Law
Little’s law, Little’s result, or Little’s theorem is perhaps the most widely used formula in queueing theory was published by J. Little [25] in 1961. It is simple to state and intuitive, widely applicable, and depends only on weak assumptions
about the properties of the queueing system. It says that the average number of customers in the system is equal to the
average arrival rate of customer to the system multiplied by the average system time per customer. Historically, Little’s law has been written as