Huge cost have been realised from the growing number of call Centres Company worldwide. There is benefit for customers as well as the multiple servers queuing system. I considered a case to serve the whole queue with a fix service rate, if there is a long queue of customers. If the customers in a queue could not reach up to the require numbers of customer to be serve as when they arrive in group then individually they could be served with different service rate. Call centres need to have an idea on how their agents are organised to have them fixed to each period to know how many agent would be needed for specified periods. To achieve a high performance there have to be an equilibrium between low waiting time and high quality services.