SOLUTION: The mean daily sales for a bookstore were $700 over the last 60 days. The standard deviation of this population is $85. What is the 95% confidence interval?

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Question 1162080: The mean daily sales for a bookstore were $700 over the last 60 days. The standard deviation of this population is $85. What is the 95% confidence interval?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the half-interval for the 95%CI is z*sigma/sqrt(n)=1.96*85/sqrt(60)
=$21.51. Add to mean and subtract from mean to get CI.
the CI is ($678.49, $721.51)