The Average Time Before Breakdown of a Machine Is Normally

question 11

Multiple Choice

The average time before breakdown of a machine is normally distributed and has a mean of nine weeks and a standard deviation of 1.5 weeks. If breakdown cost averages $1,500 and preventive maintenance costs $500, what is the optimal preventive maintenance interval?

• A)3.8 weeks
• B)8.4 weeks
• C)9.6 weeks
• D)6.9 weeks
• E)7.2 weeks

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A formal mechanism within an organization for soliciting ideas and improvements from employees.

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A performance appraisal method that collects feedback on an individual from all directions: supervisors, peers, subordinates, and occasionally clients.

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Symbolic Factor

An element that represents or signifies something beyond its literal meaning, often carrying emotional or cultural significance.