It is well known that car buyers often add accessories to their new cars. A sample of 179 Ottawa purchasers yielded a sample mean of $5000 worth of accessories added to the purchase above the base sticker price. Suppose the cost of accessories purchased for all Ottawa has a standard deviation of $1500. (a) Calculate a 95% confidence interval for the average cost of accessories on Ottawa. – Section Break - (b) Determine the margin of error in estimating the average cost of accessories on Ottawa. (c) What sample size would be required to reduce the margin of error by 50%?

It is well known that car buyers often add accessories to their new cars. A sample of 179 Ottawa purchasers yielded a sample mean of $5000 worth of accessories added to the purchase above the base sticker price. Suppose the cost of accessories purchased for all Ottawa has a standard deviation of $1500. (a) Calculate a 95% confidence interval for the average cost of accessories on Ottawa. – Section Break - (b) Determine the margin of error in estimating the average cost of accessories on Ottawa. (c) What sample size would be required to reduce the margin of error by 50%?

ENGR.ECONOMIC ANALYSIS

14th Edition

ISBN:9780190931919

Author:NEWNAN

Publisher:NEWNAN

Chapter1: Making Economics Decisions

Section: Chapter Questions

Problem 1QTC

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