1. In 2002, the average duration of incoming telephone calls to a fumiture store was 9.4 minutes. The manager wants to perform a test to determine whether this average duration of incoming calls has changed. Twenty calls to the store was randomly selected and the mean duration was 10.2 minutes with standard deviation 4.8 minutes. a) Using a 1% level of significance, test whether the mean duration of incoming calls to the store had changed. b) Construct the 95% confidence interval for the population mean duration of the incoming calls to the furniture store.

1. In 2002, the average duration of incoming telephone calls to a fumiture store was 9.4 minutes. The manager wants to perform a test to determine whether this average duration of incoming calls has changed. Twenty calls to the store was randomly selected and the mean duration was 10.2 minutes with standard deviation 4.8 minutes. a) Using a 1% level of significance, test whether the mean duration of incoming calls to the store had changed. b) Construct the 95% confidence interval for the population mean duration of the incoming calls to the furniture store.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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