Students Arrive Randomly at the Help Desk of the Computer

question 103

Multiple Choice

Students arrive randomly at the help desk of the computer lab.There is only one service agent,and the time required for inquiry varies from student to student.Arrival rates have been found to follow the Poisson distribution,and the service times follow the negative exponential distribution.The average arrival rate is 12 students per hour,and the average service rate is 20 students per hour.A student has just entered the system.How long is she expected to stay in the system?

• A)0.125 minutes
• B)0.9 minutes
• C)1.5 minutes
• D)7.5 minutes
• E)0.075 hours

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Definitions:

Direct Labour

The labour costs directly attributable to the production of goods or services, including wages for workers who physically manufacture a product.

Manufacturing Overhead

All indirect costs associated with the manufacturing process, excluding direct materials and direct labor costs.

Contribution Margin

The difference between sales revenue and variable costs, used to cover fixed expenses and then contribute to profit.

Variable Expenses

Costs that vary directly with the level of production or sales volume.