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

question 13

Multiple Choice

A laptop battery lifespan follows a normal distribution with mean μ = 22 months and a standard deviation $\sigma$ = 6 months.To test the alternative hypothesis that μ < 22 with α = .05, 36 laptop batteries are randomly selected.Assuming that μ = 21, the probability of type II error is approximately ________.

• A)-0.65
• B)0.2422
• C)0.64
• D)0.7422
• E)0.2508

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Definitions:

Horizontal Sum

In economics, the process of aggregating demand curves of different individuals to derive the market demand curve.

Inferior Good

A type of good whose demand decreases as consumers' income rises, contrary to what happens with normal goods.

Substitute Goods

Products or services that can be used in place of one another, where an increase in the price of one leads to an increase in demand for the other.

Complementary Goods

Goods that are often used together, where the use or value of one increases when used in conjunction with the other.