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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?

Solutions

Expert Solution

a)

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 5 months ago
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