The compressive strength of concrete is being studied. Four different mixing techniques are being investigated. The following data have been collected: Mixing Technique Compressive Strength (psi) 1 2600 2700 2600 2765 2 2800 2900 2985 3050 3 3200 3300 2975 3150 4 3129 3000 2865 2890 a) Perform the analysis of variance at $alpha = 0.05$ level of significance. b) Use Tukey's test to make comparison between pairs of means. Estimate the treatment effects. c) Analyze the residuals from the experiment. Draw the normal probability plot. d) Comment on the results.
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Step 1: Organize the data We have four mixing techniques (A, B, C, and D) and their respective compressive strengths: A: 2600, 2700, 2600, 2765 B: 2800, 2900, 2985, 3050 C: 3200, 3300, 2975, 3150 D: 3129, 3000, 2865, 2890 Show more…
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