The CPA Practice Advisor reports that the mean preparation fee for 2017 federal income tax returns was $273. Use this price as the population mean and assume the population standard deviation of preparation fees is $100. Use z-table. Round your answers to four decimal places. a. What is the probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean? 0.6212 b. What is the probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean? 0.7416 c. What is the probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean? 0.8804 d. Which, if any, of the sample sizes in parts (a), (b), and (c) would you recommend to have at least a 0.95 probability that the sample mean is within $16 of the population mean? None of the sample sizes in parts (a), (b), and (c) are large enough.

The CPA Practice Advisor reports that the mean preparation fee for 2017 federal income tax returns was $273. Use this price as the population mean and assume the population standard deviation of preparation fees is $100. Use z-table. Round your answers to four decimal places. a. What is the probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean? 0.6212 b. What is the probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean? 0.7416 c. What is the probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean? 0.8804 d. Which, if any, of the sample sizes in parts (a), (b), and (c) would you recommend to have at least a 0.95 probability that the sample mean is within $16 of the population mean? None of the sample sizes in parts (a), (b), and (c) are large enough.

ENGR.ECONOMIC ANALYSIS

14th Edition

ISBN:9780190931919

Author:NEWNAN

Publisher:NEWNAN

Chapter1: Making Economics Decisions

Section: Chapter Questions

Problem 1QTC

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