Throughput rate depends on the amount of time a transaction is in the system. the average residence time for a server is the average amount of time a transaction is at a server. The sum of average residence times for all servers gives the average amount of time a transaction is in the system.
In a closed system, there are always n transactions in the system. In order to obtain the system throughput, divide the number of transactions in the system, n, by the average time each transaction spends in the system.
[M2], [D4], [D5]