For these problems you should complete the 8 steps of the hypothesis testing process.State the null and alternative hypotheses.Specify alpha (a) based on the confidence level indicated.Use alpha to develop the critical value that delineates the rejection region. Remember to use a/2for two-tailed tests. Draw the curve and indicate the rejection region.Use information from the problem to compute the test statisticCalculate P-value based on test statistic.1.2.3.4.5.a) If population standard deviation or proportion use Z or normal distribution tableOne tail: 0.5 – area in non cum table.Two tailed: PV = 2* (0.5- area in non cum table)b) If sample standard deviation use t table with df = n-1.PV will be a range..e.g. 0.025 to 0.05.Compare the test statistic to the critical value. Compare the P-value to alpha.Based on your comparisons identify your decision (i.e. reject null hypothesis Ho or fail to rejectnull hypothesis Ho). Reject the null hypothesis if the test statistic is in the rejection region.Reject the null hypothesis if the P-value is smaller than alpha. The outcome of the p-value andcritical value approach will always lead to the same decision.Indicate the conclusion for the scenario6.7.8.IF Reject Ho: at % (confidence level indicated) can conclude HaIF Fail to Reject Ho: at % (confidence level indicated) can NOT conclude Ha Problem 7:The Glen Valley Steel Company manufactures steel bars. If the production process is working properly, itturns out steel bars with mean length of at least 2.8 feet. The quality control manager wants to determinewhether the production equipment needs to be adjusted. A sample of 25 bars is selected from the productionline. The sample indicates a mean length of 2.73 feet, with a sample standard deviation of 0.20 feet. Shouldadjustments be made to the equipment? Test at the 95% confidence level.

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The Glen Valley Steel Company manufactures steel bars. If the production process is working properly, it turns out steel bars with mean length of at least 2.8 feet. The quality control manager wants to determine whether the production equipment needs to be adjusted. A sample of 25 bars is selected from the production line. The sample indicates a mean length of 2.73 feet, with a sample standard deviation of 0.20 feet. Should adjustments be made to the equipment? Test at the 95% confidence level.

The Glen Valley Steel Company manufactures steel bars. If the production process is working properly, it turns out steel bars with mean length of at least 2.8 feet. The quality control manager wants to determine whether the production equipment needs to be adjusted. A sample of 25 bars is selected from the production line. The sample indicates a mean length of 2.73 feet, with a sample standard deviation of 0.20 feet. Should adjustments be made to the equipment? Test at the 95% confidence level.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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