A Design Engineer Wants to Construct a Sample Mean Chart

question 15

Multiple Choice

A design engineer wants to construct a sample mean chart for controlling the service life of a halogen headlamp his company produces. He knows from numerous previous samples that this service life is normally distributed with a mean of 500 hours and a standard deviation of 20 hours. On three recent production batches, he tested service life on random samples of four headlamps, with these results

What is the standard deviation of the sampling distribution of sample means for whenever service life is in control?

• A)5 hours
• B)6.67 hours
• C)10 hours
• D)11.55 hours
• E)20 hours

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Definitions:

Aggressive Optimism

A mindset or strategy characterized by a high degree of confidence and assertiveness in action or decision-making, often in the context of investments or business growth.

Conservatism

An accounting principle that dictates reporting expenses and liabilities as soon as possible, but revenue only when it is ensured.

Top-Down Plan

A planning approach where decision making starts at the highest level of management and cascades down to lower levels.

Bottom-Up Plan

A planning approach that starts at the operational level, with detailed tasks and schedules, and integrates them into an overall strategic plan.