Facebook: A study showed that two years ago, the mean time spent per visit to Facebook was 20.8 minutes, Assume the standard devlation is o= 8.0minutes. Suppose that a simple random sample of 107 visits was selected this year and has a sample mean of x= 18.8 minutes. A social scientist is interestedto know whether the mean time of Facebook visits has decreased. Use the a=0.10 level of significance and the critical value method with the table.(a) State the appropriate null and alternate hypotheses.(b) Compute the value of the test statistic.(c) State a conclusion. Use the a = 0.10 level of significance. Part 2 of 5Find the critical value(s). Round the answer(s) to three decimal places, if necessary. If there is more than one critical value, separate them with commas.Critical value(s):Part: 2/5Part 3 of 5(b) Compute the value of the test statistic. Round the answer to at least two decimal places.

We have given that Sample size n= 107 Sample mean = 18.8 Population standard deviation = 8.0

Answered: Facebook: A study showed that two years…

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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Facebook: A study showed that two years ago, the mean time spent per visit to Facebook was 20.8 minutes. Assume the standard deviation is a=8.0 minutes. Suppose that a simple random sample of 107 visits was selected this year and has a sample mean ofx18.8 minutes. A social scientist is interestec to know whether the mean time of Facebook visits has decreased. Use the a =0.10 level of significance and the critical value method with the table. (a) State the appropriate null and alternate hypotheses. (b) Compute the value of the test statistic. (c) State a conclusion. Use the u =0.10 level of significance. Part: 0/5 Part 1 of 5 (a) State the null and alternate hypotheses. D-0 This hypothesis test is a (Choose one) v test. noht-talled
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