The lifetime (in years) of a laptop is known to be normally distributed with unknown mean lifetime µ and σ = = 0.5 year. A random sample of 25 laptops has an average lifetime of x = 3.2 years. (a) Construct a 95% two-sided confidence interval on the mean lifetime. (b) Construct a 95% lower-confidence bound on the mean lifetime. (c) Construct a 90% and 99% two-sided confidence interval on the mean lifetime and compare the width of these confidence intervals to the width in (a). What conclusion can you draw from this comparison?

The lifetime (in years) of a laptop is known to be normally distributed with unknown mean lifetime µ and σ = = 0.5 year. A random sample of 25 laptops has an average lifetime of x = 3.2 years. (a) Construct a 95% two-sided confidence interval on the mean lifetime. (b) Construct a 95% lower-confidence bound on the mean lifetime. (c) Construct a 90% and 99% two-sided confidence interval on the mean lifetime and compare the width of these confidence intervals to the width in (a). What conclusion can you draw from this comparison?

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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