Managers of an industrial plant want to determine which of two types of fuel, gas or electric, is more cost efficient (measured in cost per unit of energy). Independent random samples were taken of plants using electricity and plants using gas. These samples consisted of 9 plants using electricity, which had a mean cost per unit of $50 and standard deviation of $8.58, and 15 plants using gas, which had a mean of $56.5 and standard deviation of $8.5. Assume that the populations of costs per unit are normally distributed for each type of fuel, and assume that the variances of these populations are equal. Construct a 99% confidence interval for the difference u,-H, between the mean cost per unit for plants using electricity, µ, and the mean cost per unit for plants using gas, µɔ. Then complete the table below. 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.) What is the lower limit of the 99% confidence interval? What is the upper limit of the 99% confidence interval?

Managers of an industrial plant want to determine which of two types of fuel, gas or electric, is more cost efficient (measured in cost per unit of energy). Independent random samples were taken of plants using electricity and plants using gas. These samples consisted of 9 plants using electricity, which had a mean cost per unit of $50 and standard deviation of $8.58, and 15 plants using gas, which had a mean of $56.5 and standard deviation of $8.5. Assume that the populations of costs per unit are normally distributed for each type of fuel, and assume that the variances of these populations are equal. Construct a 99% confidence interval for the difference u,-H, between the mean cost per unit for plants using electricity, µ, and the mean cost per unit for plants using gas, µɔ. Then complete the table below. 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.) What is the lower limit of the 99% confidence interval? What is the upper limit of the 99% confidence interval?

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Description: Managers of an industrial plant want to determine which of two types of fuel, gas or electric, is more cost efficient (measured in cost per unit of energy). Independent random samples were taken of plants using electricity and plants using gas. Thes

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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