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 long- distance calls has changed. Fifty calls, originating from the town, was randomly selected and the following summary minutes. Σx= 205 Σ(x - ): 56.43 %3D 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
icon
Related questions
Topic Video
Question

Please answer the questions attached

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 long- distance calls has
changed. Fifty calls, originating from the town, was randomly selected and the following
summary minutes.
Σx= 205 Σ(x - ): 56.43
%3D
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.
Transcribed Image Text: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 long- distance calls has changed. Fifty calls, originating from the town, was randomly selected and the following summary minutes. Σx= 205 Σ(x - ): 56.43 %3D 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.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps

Blurred answer
Knowledge Booster
Permutation and Combination
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman