(a) A technical report has the following summary information for fracture strength (in MPa) of n = 169 ceramic bars fired in a particular kiln: š = 89.10, s = 3.73. (i) Using a confidence level of 95%, calculate a two-side confidence interval for true average fracture strength. Then justify whether it appears that the average fracture strength has been precisely estimated. (ii) Suppose the investigators had believed a priori that the population standard deviation was about 4 MPa. Based on this supposition, assume how large a sample would have been required to estimate u to within 0.5 MPa. Use a confidence level of 95%.

(a) A technical report has the following summary information for fracture strength (in MPa) of n = 169 ceramic bars fired in a particular kiln: š = 89.10, s = 3.73. (i) Using a confidence level of 95%, calculate a two-side confidence interval for true average fracture strength. Then justify whether it appears that the average fracture strength has been precisely estimated. (ii) Suppose the investigators had believed a priori that the population standard deviation was about 4 MPa. Based on this supposition, assume how large a sample would have been required to estimate u to within 0.5 MPa. Use a confidence level of 95%.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

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Question

(a) A technical report has the following summary information for fracture strength
(in MPa) of n = 169 ceramic bars fired in a particular kiln: i = 89.10, s = 3.73.
(i) Using a confidence level of 95%, calculate a two-side confidence interval
for true average fracture strength. Then justify whether it appears that the
average fracture strength has been precisely estimated.
(ii) Suppose the investigators had believed a priori that the population standard
deviation was about 4 MPa. Based on this supposition, assume how large a
sample would have been required to estimate u to within 0.5 MPa. Use a
confidence level of 95%.

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