Using the simple random sample of weights of women from a data set, we obtain these sample statistics: nequals45 and x overbarequals148.79 lb. research from other sources suggests that the population of weights of women has a standard deviation given by sigmaequals31.37 lb. a. find the best point estimate of the mean weight of all women. b. find a 90% confidence interval estimate of the mean weight of all women.

(141.1, 156.48)

Step-by-step explanation:

Given sample statistics :

a) We know that the best point estimate of the population mean is the sample mean.

Therefore, the best point estimate of the mean weight of all women =

b) The confidence interval for the population mean is given by :-

, where E is the margin of error.

Formula for Margin of error :-

Given : Significance level :

Critical value :

Margin of error :

Now, the 90% confidence interval for the population mean will be :-

Hence, the 90% confidence interval estimate of the mean weight of all women= (141.1, 156.48)

5x+10 is the correct one

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