13. In an experiment to see whether the amount of coverage of light-blue interior latex paint depends either on the brand of paint or on the brand of roller used, one gallon of
each of four brands of paint was applied using each of three brands of roller, resulting
in the following data (number of square feet covered).
1
1454
Paint 2 446
Brand 3 439
4 444
Roller Brand
2
446
444
442
437
3
451
447
444
443
a. Construct the ANOVA table. (Hint: The computations can be expedited by
subtracting 400 (or any other convenient number) from each observation. This
does not affect the final results.)
b. State and test hypotheses appropriate for deciding whether paint brand has any
effect on coverage. Use a = 0.05.
c. Repeat part (b) for brand of roller.