At a manufacturing assembly line, 30 jobs arrive perhour. Each job must pass through two production stages:stage 1 and stage 2. Stage 1 takes an average of 1 minute tocomplete, and 1 worker is available to perform stage 1.After completing stage 1, the job immediately passes tostage 2. Stage 2 takes an average of 2 minutes to complete,and 2 workers are available to work on stage 2. Aftercompleting stage 2, each job is inspected. Inspection takesan average of 3 minutes, and 3 workers are available toperform inspection. After inspection, 10% of the jobs mustbe returned to stage 1, and they then repeat both stages 1and 2. After inspection, 20% of all jobs return to stage 2 andrepeat stage 2. Assume that interarrival times and servicetimes are exponential.a What is the average time a job spends in the systemfrom arrival to completion?b What percentage of the time is each worker busy?

At a manufacturing assembly line, 30 jobs arrive perhour. Each job must pass through two production stages:stage 1 and stage 2. Stage 1 takes an average of 1 minute tocomplete, and 1 worker is available to perform stage 1.After completing stage 1, the job immediately passes tostage 2. Stage 2 takes an average of 2 minutes to complete,and 2 workers are available to work on stage 2. Aftercompleting stage 2, each job is inspected. Inspection takesan average of 3 minutes, and 3 workers are available toperform inspection. After inspection, 10% of the jobs mustbe returned to stage 1, and they then repeat both stages 1and 2. After inspection, 20% of all jobs return to stage 2 andrepeat stage 2. Assume that interarrival times and servicetimes are exponential.a What is the average time a job spends in the systemfrom arrival to completion?b What percentage of the time is each worker busy?

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter4: Linear Programming Models

Section: Chapter Questions

Problem 107P

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