### Statistical Hypothesis Testing ExampleA computer manufacturing company claims that only 7.2% of their computers are returned. Kelly suspects that the company is underreporting and believes the true proportion is higher. She decides to test this hypothesis at a significance level ($\alpha$) of 0.01. Kelly samples 300 computers and finds that 25 are returned. Assume a normal sampling distribution.#### (a) Null and Alternative Hypotheses- **Null Hypothesis ($H_0$)**: $p = 0.072$- **Alternative Hypothesis ($H_A$)**: $p > 0.072$#### (b) Test StatisticKelly calculates the test statistic, which should be rounded to two decimal places.#### (c) p-valueUsing a statistical table, she finds the p-value, rounded to four decimal places.#### (d) Decision Based on p-valueKelly decides to "fail to reject" the null hypothesis based on the p-value.#### (e) ConclusionThe data "does not provide" sufficient evidence to conclude that the true proportion of computers returned is higher than the company claims.This exercise illustrates the process of hypothesis testing in statistics, emphasizing the importance of understanding how to interpret statistical data to make informed decisions.

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Answered: A computer manufacturing company claims…

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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