6. The manufacturer of the ColourSmart television claims that 85% of its sets la at least five years without needing a single repair. In order to test this claim, a consumer group randomly selected 400 consumers who have owned a ColourSmart television set for five years. Of these 400 consumers, 65 say that their ColourSmart television sets did need at least one repair. a. Obtain the point estimate for the proportion of all ColourSmart television sets that have lasted at least five years without needing a single repair. * Your answer b. Determine whether the condition is satisfied to use the large sample formula of the confidence interval of the population proportion. (Check the assumption to use Z distribution) Your answer C. Find a 99% confidence interval for the true proportion of all ColourSmart television sets that have lasted at least five years without needing a single repair. (Type your answer in this format: Margin error%3D 99% CI =

6. The manufacturer of the ColourSmart television claims that 85% of its sets la at least five years without needing a single repair. In order to test this claim, a consumer group randomly selected 400 consumers who have owned a ColourSmart television set for five years. Of these 400 consumers, 65 say that their ColourSmart television sets did need at least one repair. a. Obtain the point estimate for the proportion of all ColourSmart television sets that have lasted at least five years without needing a single repair. * Your answer b. Determine whether the condition is satisfied to use the large sample formula of the confidence interval of the population proportion. (Check the assumption to use Z distribution) Your answer C. Find a 99% confidence interval for the true proportion of all ColourSmart television sets that have lasted at least five years without needing a single repair. (Type your answer in this format: Margin error%3D 99% CI =

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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