In 2015, the average duration of long-distance telephone calls from a certain townwas 3.9 minutes. A telephone company wants to perform a test to determinewhether this average duration of long- distance calls has changed. Fifty calls,originating from the town, was randomly selected and the following summaryminutes.Σχ-205E(x-x)2 =56.43a) Calculate the sample mean, x.b) Calculate the sample standard deviationc) Using the p value approach at the 1% level of significance, test whether themean duration of long-distance calls from the town had increased.d) Construct the 99% confidence interval for the population mean duration ofthe long-distance calls from the town.

a). Given: μ=Population mean=3.9n=Sample size=50∑x=205∑(x-x¯)2=56.43 The calculation of sample mean…

Σχ-205 E(x-x)2 =56.43 a) Calculate the sample mean, x. b) Calculate the sample standard deviation c) Using the p value approach at the 1% level of significance, test whether the mean duration of long-distance calls from the town had increased. d) Construct the 99% confidence interval for the population mean duration of the long-distance calls from the town.

Σχ-205 E(x-x)2 =56.43 a) Calculate the sample mean, x. b) Calculate the sample standard deviation c) Using the p value approach at the 1% level of significance, test whether the mean duration of long-distance calls from the town had increased. d) Construct the 99% confidence interval for the population mean duration of the long-distance calls from the town.

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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