An experiment was performed to determine whether the annealing temperature of ductile iron affects its tensile strength. Five specimens were annealed at each of four temperatures. The tensile strength (in ksi) was measured for each. The results are presented in the following table. Machine Temperature(°C ) Sample Values 750 17.89 19.72 20.88 19.63 18.68 800 16.01 20.04 18.10 20.28 20.53 850 16.66 17.38 14.49 18.21 15.58 900 16.93 14.49 16.15 15.53 13.25 Perform the analysis of variance(ANOVA) at the 0.05 level of significance and indicate whether or not there are differences among the mean strengths?
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Given data: n = 5 (number of specimens per temperature) k = 4 (number of temperatures) SST = 41.21746 SSB = 4.3800055 SSW = 36.8374545 dfB = k - 1 = 4 - 1 = 3 dfW = N - k = 20 - 4 = 16 MSB = SSB / dfB = 4.3800055 / 3 = 1.46000183 MSW = SSW / dfW = 36.8374545 / Show more…
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