A manufacturing company produces steel wires with an average strength of 1350. The company then wishes to increase the strength of the steel wires by changing its cementite decomposition. A random sample of 10 steel wires using the new decomposition is collected and tested. The manufacturer will change the cementite decomposition of the steel wires to a new decomposition unless a decrease in the strength of the steel wire in new decomposition is significant. Assuming that the strength of the steel wire is approximately normal, and standard deviation is not affected. a. At 5% significance level, is there evidence that the steel manufacturing company should continue with the new decomposition if the average strength of the 10 steel wires of new decomposition is 1400, with a standard deviation of 27. b. Using the result in (i), what is the maximum average strength required to return to the old composition of steel wires?

A manufacturing company produces steel wires with an average strength of 1350. The company then wishes to increase the strength of the steel wires by changing its cementite decomposition. A random sample of 10 steel wires using the new decomposition is collected and tested. The manufacturer will change the cementite decomposition of the steel wires to a new decomposition unless a decrease in the strength of the steel wire in new decomposition is significant. Assuming that the strength of the steel wire is approximately normal, and standard deviation is not affected. a. At 5% significance level, is there evidence that the steel manufacturing company should continue with the new decomposition if the average strength of the 10 steel wires of new decomposition is 1400, with a standard deviation of 27. b. Using the result in (i), what is the maximum average strength required to return to the old composition of steel wires?

College Algebra

7th Edition

ISBN:9781305115545

Author:James Stewart, Lothar Redlin, Saleem Watson

Publisher:James Stewart, Lothar Redlin, Saleem Watson

Chapter1: Equations And Graphs

Section: Chapter Questions

Problem 10T: Olympic Pole Vault The graph in Figure 7 indicates that in recent years the winning Olympic men’s...

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