Q5 (a) A manufacturing company claims that the mean lifetime of bulbs produced was at least 160 hours. In a random sample of 100 bulbs produced, the sample mean lifetime of bulbs was 150 hours and the sample standard deviation was 25 hours. (i) Construct a 95% confidence interval for the mean lifetime of bulbs produced. (ii) Construct a 99% confidence interval for the mean lifetime of bulbs produced. (iii) Calculate the width of confidence interval in (a) and (b). Interpret the result.

Q5 (a) A manufacturing company claims that the mean lifetime of bulbs produced was at least 160 hours. In a random sample of 100 bulbs produced, the sample mean lifetime of bulbs was 150 hours and the sample standard deviation was 25 hours. (i) Construct a 95% confidence interval for the mean lifetime of bulbs produced. (ii) Construct a 99% confidence interval for the mean lifetime of bulbs produced. (iii) Calculate the width of confidence interval in (a) and (b). Interpret the result.

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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