A manufacturer of carpet wanted to reduce the number of flaws per square yard of carpet. Data gathered from quality control measures indicated that Brand A typically had 2.5 flaws per square yard. A mechanical engineer for the company developed a modification of the current process that she thought might reduce the number of flaws. To determine if this was true, one of the machines in the plant was modified according to her specifications. A sample of 30 square yards of carpet was analyzed for flaws. The sample yielded a mean of 2.2 flaws per square yard. Assume the standard deviation of the measurements is 0.66. A. Not statistically significant at the 0.05 level B. Not practically significant at the 0.05 level C. statistically significant at the 0.05 level D.Practically significant at the 0.05 level

A manufacturer of carpet wanted to reduce the number of flaws per square yard of carpet. Data gathered from quality control measures indicated that Brand A typically had 2.5 flaws per square yard. A mechanical engineer for the company developed a modification of the current process that she thought might reduce the number of flaws. To determine if this was true, one of the machines in the plant was modified according to her specifications. A sample of 30 square yards of carpet was analyzed for flaws. The sample yielded a mean of 2.2 flaws per square yard. Assume the standard deviation of the measurements is 0.66. A. Not statistically significant at the 0.05 level B. Not practically significant at the 0.05 level C. statistically significant at the 0.05 level D.Practically significant at the 0.05 level

Linear Algebra: A Modern Introduction

4th Edition

ISBN:9781285463247

Author:David Poole

Publisher:David Poole

Chapter7: Distance And Approximation

Section7.3: Least Squares Approximation

Problem 31EQ

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