In 2015, the average duration of long-distance telephone calls from a certain town was 3.9 minutes.A telephone company wants to perform a test to determine whether this average duration of longdistance calls has changed. Fifty calls, originating from the town, was randomly selected and the following summary minutes. ∑ ? = 205 ∑(? − ?̅) 2 = 56.43 a) 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. b) Construct the 99% confidence interval for the population mean duration of the long-distance calls from the town.

In 2015, the average duration of long-distance telephone calls from a certain town was 3.9 minutes.A telephone company wants to perform a test to determine whether this average duration of longdistance calls has changed. Fifty calls, originating from the town, was randomly selected and the following summary minutes. ∑ ? = 205 ∑(? − ?̅) 2 = 56.43 a) 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. b) Construct the 99% confidence interval for the population mean duration of the long-distance calls from the town.

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

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.6: Summarizing Categorical Data

Problem 30PPS

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