A customer service centre of a local mobile phone company has customers arriving exponentially with an average of 5 minutes. After entering the company, all customers go directly to the ticket machine to take an ordered ticket. They take 1 ± 0.5 minute uniformly to do so. Then they go to the waiting area and sit down. The customers are waiting to request 1 of 3 representatives. Historical data shows that 40% of the customers want to see the representative of Network Service, 40% want to see the representative of Repair Service, and 20% want to see the representative of Billing Service. When the desired representative is available, a staff will escort the customer from the waiting area to the representative. When seeing the representative of Network Service, the visit lasts to be normally distributed with a mean of 7 minutes and a standard deviation of 2 minutes. When seeing the representative of Repair Service, the visit takes to be normally distributed with a mean of 10 minutes and a standard deviation of 2 minutes. The visit of representative of Billing Service lasts to be normally distributed with a mean of 5 and a standard deviation of 1.
Some of the customers also see the Promotion Service after they have finished their servicing with the representatives of Network Service, Repair Service or Billing Service. An Assistant Manager will escort such customers to his room and introduces the promotion package individually. The introduction takes to be normally distributed with a mean of 10 minutes and a standard deviation of 3 minutes.
Marketing Department found that 10% of the customers that enquire Network Service listen to the introduction of Promotion Service, 20% that see the Repair Service listen to the introduction of Promotion Service, and 5% who have seen the representative of Billing Service listen to the introduction of Promotion Service. After listening the introduction of promotion with the Assistant Manager, the customers leave.
Run the model from 9:00am to 1:00pm, with 5 replications, view the results, then answer the following:
.a) What is the % of the staff’s time is spent in use?
.b) What is the % of the Assistant Manager’s time is spent in use?
.c) What about the utilization of the 3 representatives?
.d) On average, how long do customers wait in the waiting area?
.e) What was the most number of customers waiting to see the representative at one time?
