Yellow stains on white clothing are stubborn discolorationsbelieved to result from oxidated body oils that have reactedchemically with clothing’s cellulose fibers (as if it were a dye).In as little as one week, there reaction can permanently discolorwith clothing with an ugly yellow stain and at this point the mostpotent laundry product will usually be of little value in removingthem. Suppose researchers at the Department of Textiles and Apparelat Cornell University, experimenting with new experimentalformulations to remove stains, washed six discolored strips in eachof three experimental formulations, and the results as followsColoring rating (after washing) 0 = Dark Yellow, the initial shade20 = Pure White-All washed strips were matched to a color chart, aseries of increasingly lighter shade, and rated from 0 to 20.Formulation X Y Z 10 8 11 9 10 12 10 12 14 12 9 11 8 10 10 11 8 14Three Different Formulations were tested a) Calculate by hand theaverage color rating and variance for each group b) Assuming validrandom samples, test at 5% level significance whether differencesamong the three-sample means can be attributed to chancefluctuation or, indeed, to actual differences in thestain-eliminating ability of the three formulations. ( hint: findthe F-ratio) c) Briefly discuss the implications of these results.Need to solve by hand. Please help!
