Mid-West Publishing Company publishes college textbooks. Thecompany operates an 800 telephone number whereby potential adopterscan ask questions about forthcoming texts, request examinationcopies of texts, and place orders. Currently, two extension linesare used, with two representatives handling the telephoneinquiries. Calls occurring when both extension lines are being usedreceive a busy signal; no waiting is allowed. Each representativecan accommodate an average of 11 calls per hour. The arrival rateis 22 calls per hour.
- How many extension lines should be used if the company wants tohandle 90% of the calls immediately?
- What is the probability that a call will receive a busy signalif your recommendation in part (a) is used? If required, round youranswer to four decimal places.
- What number of calls, in decimal form, receive a busy signalfor the current telephone system with two extension lines? Ifrequired, round your answer to four decimal places.
