A Design Engineer Wants to Construct a Sample Mean Chart

question 54

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

If he uses upper and lower control limits of 520 and 480 hours, what is his risk (alpha) of concluding that service life is out of control when it is actually under control (Type I error) ?

• A)0.0026
• B)0.0456
• C)0.3174
• D)0.6826
• E)0.9544

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Definitions:

Somatic Symptom Disorder

A mental disorder characterized by an excessive focus on physical symptoms, such as pain or fatigue, which cause significant distress or problems in functioning.

Treatment Prognosis

An assessment of the likely course and outcome of a disease or condition following treatment.

Professional Help

Assistance offered by certified or licensed professionals in a specific field, especially in healthcare, legal, or educational services.

Did Diagnoses

Likely a typing error, but if it meant "DID diagnoses," it would refer to the process of identifying Dissociative Identity Disorder, a complex psychological condition.