A Laptop Battery Lifespan Follows a Normal Distribution with Mean $\sigma$

question 66

Multiple Choice

A laptop battery lifespan follows a normal distribution with mean μ = 20 months and a standard deviation $\sigma$ = 6 months.To test the alternative hypothesis that μ > 20 with α = .05, 36 laptop batteries are randomly selected.Assuming that μ = 21, the probability of type II error is approximately ________.

• A)0.00
• B)0.2595
• C)0.2036
• D)0.6449
• E)0.7405

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Definitions:

Spoilage

The portion of raw materials or inventory that becomes unusable or unsellable during production.

Machine Breakdowns

Instances when machinery or equipment fails to operate, causing interruptions in production or operations.

Cost Variance

The differences between actual and standard costs.

Standard Cost

A detailed estimate of what a product should cost.