9. (a) A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1000 hours. A homeowner wonders if the actual mean lifetime of bulbs is different from 1000 hours. The homeowner selects 40 bulbs and finds the mean lifetime to be 990 hours with a standard deviation of s = 80 hours. Test the manufacturer's claim. Use the critical value method and a = 0.05. (b) You work for a consumer advocate agency and want to find the mean lifetime of fluorescent bulbs. You randomly select 40 bulbs and find that the mean lifetime of these bulbs is 990 hours with a standard deviation of s = 80 hours. Calculate a 95% confidence interval for the population mean lifetime. (c) Explain how the above two statistical procedures lead to the same conclusion.

9. (a) A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1000 hours. A homeowner wonders if the actual mean lifetime of bulbs is different from 1000 hours. The homeowner selects 40 bulbs and finds the mean lifetime to be 990 hours with a standard deviation of s = 80 hours. Test the manufacturer's claim. Use the critical value method and a = 0.05. (b) You work for a consumer advocate agency and want to find the mean lifetime of fluorescent bulbs. You randomly select 40 bulbs and find that the mean lifetime of these bulbs is 990 hours with a standard deviation of s = 80 hours. Calculate a 95% confidence interval for the population mean lifetime. (c) Explain how the above two statistical procedures lead to the same conclusion.

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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