Lemma
MediumSampling distributions
OpenStax, Statistics §7.3 Using the Central Limit Theorem · Exercise 40 · Statistics · Sampling distributions

Using the Central Limit Theorem · Exercise 40

For each problem, wherever possible, provide graphs and use a calculator.

NeverReady batteries has engineered a newer, longer-lasting AAA battery. The company claims this battery has an average life span of 17 hours with a standard deviation of 0.8 hours. Your statistics class questions this claim. As a class, you randomly select 30 batteries and find that the sample mean life span is 16.7 hours. If the process is working properly, what is the probability of getting a random sample of 30 batteries in which the sample mean life span is 16.7 hours or less? Is the company’s claim reasonable?

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OpenStax, Statistics · §7.3 Using the Central Limit Theorem · Exercise 40

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