8.44 The mean time taken to design a house plan by 40 architects was found to...

8.44 The mean time taken to design a house plan by 40 architects was found to be 23 hours with a standard deviation of 3.75 hours.

a. Construct a 98% confidence interval for the population mean μ.

b. Suppose the confidence interval obtained in part a is too wide. How can the width of this interval be reduced? Describe all possible alternatives. Which alternative is the best and why?

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Expert Solution

b) Increase the sample size. The more data in the sample, the smaller the confidence interval.With more data, there are more chance of the sample being a pretty good match to the wholepopulation and, therefore, of its mean being similar to the true population value.

milcah answered 3 days ago

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