# Question: According to an estimate 2 years ago the average age

According to an estimate, 2 years ago the average age of all CEOs of medium-sized companies in the United States was 58 years. Jennifer wants to check if this is still true. She took a random sample of 70 such CEOs and found their mean age to be 55 years with a standard deviation of 6 years.

a. Suppose that the probability of making a Type I error is selected to be zero. Can you conclude that the current mean age of all CEOs of medium-sized companies in the Untied States is different from 58 years?

b. Using a 1% significance level, can you conclude that the current mean age of all CEOs of medium sized companies in the United States is different from 58 years? Use both approaches.

a. Suppose that the probability of making a Type I error is selected to be zero. Can you conclude that the current mean age of all CEOs of medium-sized companies in the Untied States is different from 58 years?

b. Using a 1% significance level, can you conclude that the current mean age of all CEOs of medium sized companies in the United States is different from 58 years? Use both approaches.

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