manager of a computer software store thinks that, even though the average number of buyers or clients is approximately the same as 5 years ago, the number of buyers or clients is more volatile that it was 5 years ago. In a sample of 26 weeks from 5 years ago, the standard deviation of buyers was 31 per week while in a sample of 21 weeks over the past year the standard deviation is 26 per week. Test the hypothesis at the 2.5% level of significance that the variance has increased from 5 years ago.

manager of a computer software store thinks that, even though the average number of buyers or clients is approximately the same as 5 years ago, the number of buyers or clients is more volatile that it was 5 years ago. In a sample of 26 weeks from 5 years ago, the standard deviation of buyers was 31 per week while in a sample of 21 weeks over the past year the standard deviation is 26 per week. Test the hypothesis at the 2.5% level of significance that the variance has increased from 5 years ago.

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.5: Comparing Sets Of Data

Problem 4CYU

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Question

A manager of a computer software store thinks that, even though the average number of buyers or clients is approximately the same as 5 years ago, the number of buyers or clients is more volatile that it was 5 years ago. In a sample of 26 weeks from 5 years ago, the standard deviation of buyers was 31 per week while in a sample of 21 weeks over the past year the standard deviation is 26 per week. Test the hypothesis at the 2.5% level of significance that the variance has increased from 5 years ago.

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