05 (а)A manufacturing company claims that the mean lifetime of bulbs producedwas at least 160 hours. In a random sample of 100 bulbs produced, thesample mean lifetime of bulbs was 150 hours and the sample standarddeviation was 25 hours.(i)Construct a 95% confidence interval for the mean lifetime of bulbsproduced.(ii)produced.Construct a 99% confidence interval for the mean lifetime of bulbs(iii)Calculate the width of confidence interval in (a) and (b). Interpret theresult.

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. (a) (i) produced. Construct a 95% confidence interval for the mean lifetime of bulbs (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.

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. (a) (i) produced. Construct a 95% confidence interval for the mean lifetime of bulbs (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.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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