The owner of a local Karaoke Bar has recently surveyed a random sample of n = 300 customers of the bar.She would now like to determine whether or not the mean age of her customers is over 35.If so,she plans to alter the entertainment to appeal to an older crowd.If not,no entertainment changes will be made.If she wants to be 99% confident in her decision,what rejection region she use if the population standard deviation σ is known? A)Reject H₀ if z 2.58

Question

The owner of a local Karaoke Bar has recently surveyed a random sample of n = 300 customers of the bar.She would now like to determine whether or not the mean age of her customers is over 35.If so,she plans to alter the entertainment to appeal to an older crowd.If not,no entertainment changes will be made.If she wants to be 99% confident in her decision,what rejection region she use if the population standard deviation σ is known? A)Reject H₀ if z < −2.33 B)Reject H₀ if z < −2.58 C)Reject H₀ if z > 2.33 D)Reject H₀ if z > 2.58

Quizplus · Accepted Answer

Since the owner wants to determine if the mean age is over 35, this is a one-tailed test. For a 99% confidence level in a one-tailed test, the critical z-value is 2.33. Therefore, the rejection region for the hypothesis that the mean age is over 35 would be if the calculated z-value is greater than 2.33.

The Owner of a Local Karaoke Bar Has Recently Surveyed