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How large a sample should be selected to provide a 95% confidence interval with a margin of error of 8? Assume that the population standard deviation is 20. Round your answer to next whole number.

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter13: Regression And Forecasting Models

Section13.4: Multiple Regression Models

Problem 17P: The owner of a restaurant in Bloomington, Indiana, has recorded sales data for the past 19 years. He...

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How large a sample should be selected to provide a 95% confidence interval with a margin of error of 8? Assume that the population standard deviation is 20.
Round your answer to next whole number.

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