A manufacturing facility stores spare parts for maintenance in a storage facility. Throughout the working day, manufacturing personnel go to the storage facility to pick up supplies needed for their jobs. The storage facility employees receive a request for supplies, on average, every five minutes from the manufacturing personnel. The average request requires 3.2 minutes to fill a request. Manufacturing personnel are paid $29.50 per hour and storage facility employees are paid $18.75 per hour. The storage facility operates 8 hours per day. Base your costs on an 8-hour workday, the given arrival and service rates, and the fact that when the manufacturing personnel are at the storage site picking up parts – they are unable to complete their normal job in manufacturing. a) What is the system cost per day (to the nearest $) if there is only 1 storage facility employee working? b) What is the system cost per day (to the nearest $) if there are 2 storage facility employees working? c) What is the system cost per day (to the nearest $) if there are 3 storage facility employees working? d) What is the optimal number of warehouse employees to staff the warehouse?

A manufacturing facility stores spare parts for maintenance in a storage facility. Throughout the working day, manufacturing personnel go to the storage facility to pick up supplies needed for their jobs. The storage facility employees receive a request for supplies, on average, every five minutes from the manufacturing personnel. The average request requires 3.2 minutes to fill a request. Manufacturing personnel are paid $29.50 per hour and storage facility employees are paid $18.75 per hour. The storage facility operates 8 hours per day. Base your costs on an 8-hour workday, the given arrival and service rates, and the fact that when the manufacturing personnel are at the storage site picking up parts – they are unable to complete their normal job in manufacturing. a) What is the system cost per day (to the nearest $) if there is only 1 storage facility employee working? b) What is the system cost per day (to the nearest $) if there are 2 storage facility employees working? c) What is the system cost per day (to the nearest $) if there are 3 storage facility employees working? d) What is the optimal number of warehouse employees to staff the warehouse?

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter12: Queueing Models

Section12.4: Important Queueing Relationships

Problem 6P

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