A light bulb manufacturer wants to compare the mean lifetimes of two of its light bulbs, model A and model B. Independent random samples of the two models were taken. Analysis of 12 bulbs of model A showed a mean lifetime of 1203 hours and a standard deviation of 114 hours. Analysis of 11 bulbs of model B showed a mean lifetime of 1396 hours and a standard deviation of 105 hours. Assume that the populations of lifetimes for each model are normally distributed and that the variances of these populations are equal. Construct a 95% confidence interval for the difference µ, -µ, between the mean lifetime u, of model A bulbs and the mean lifetime , of model B bulbs. Then find the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your responses to at least two decimal places. (If necessary, consult a list of formulas.) Lower limit:I ? Upper limit:

A light bulb manufacturer wants to compare the mean lifetimes of two of its light bulbs, model A and model B. Independent random samples of the two models were taken. Analysis of 12 bulbs of model A showed a mean lifetime of 1203 hours and a standard deviation of 114 hours. Analysis of 11 bulbs of model B showed a mean lifetime of 1396 hours and a standard deviation of 105 hours. Assume that the populations of lifetimes for each model are normally distributed and that the variances of these populations are equal. Construct a 95% confidence interval for the difference µ, -µ, between the mean lifetime u, of model A bulbs and the mean lifetime , of model B bulbs. Then find the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your responses to at least two decimal places. (If necessary, consult a list of formulas.) Lower limit:I ? Upper limit:

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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