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 unitof energy). Independent random samples were taken of plants using electricity and plants using gas. These samples consisted of 10 plantsusing electricity, which had a mean cost per unit of $60.80 and standard deviation of $8.53, and 9 plants using gas, which had a mean of$59.20 and standard deviation of $8.75. Assume that the populations of costs per unit are normally distributed for each type of fuel, andassume that the variances of these populations are equal. Construct a 95% confidence interval for the difference u, -u, between the meancost per unit for plants using electricity, u,, and the mean cost per unit for plants using gas, u,. Then find the lower limit and upper limit ofthe 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:|?Upper limit:

Sample mean for electricity(x1)=60.80 Standard deviation for electricity(s1)=8.53 Sample size for…

Answered: Managers of an industrial plant want to…

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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Research has shown that, for baseball players, good hip range of motion results in improved performance and decreased body stress. A research article reported on a study of independent samples of 40 professional pitchers and 40 professional position players. For the pitchers, the sample mean hip range of motion was 75.5 degrees and the sample standard deviation was 5.8 degrees, whereas the sample mean and sample standard deviation for position players were 79.1 degrees and 7.1 degrees, respectively. Assuming that the two samples are representative of professional baseball pitchers and position players, test hypotheses appropriate for determining if there is convincing evidence that the mean range of motion for pitchers is less than the mean for position players. (Use ? = 0.05. Use ?1 for pitchers and ?2 for position players.) State the appropriate null and alternative hypotheses. Find the test statistic and P-value. (Use SALT. Round your test statistic to one decimal place and…
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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 10 plants using electricity, which had a mean cost per unit of $53.50 and standard deviation of $8.19 , and 11 plants using gas, which had a mean of $55.40 and standard deviation of $8.23 . 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 95% confidence interval for the difference −μ1μ2 between the mean cost per unit for plants using electricity, μ1 , and the mean cost per unit for plants using gas, μ2 . 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…
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