An engineer suspects that the surface finish of metal parts is influenced by the type of paint used and the drying time. He selected three drying times€”20, 25, and 30 minutes€”and used two types of paint. Three parts are tested with each combination of paint type and drying time. The data are as follows:

(a) State the hypotheses of interest in this experiment.

(b) Test the hypotheses in part (a) and draw conclusions using the analysis of variance with α = 0.05.

(c) Analyze the residuals from this experiment.

Transcribed Image Text:

Drying Time (min) Paint 25 30 1 74 73 78 64 61 85 50 44 92 92 98 66 86 73 45 68 88 85