Six samples of four different types of milk Puerto Rico were analyzed for protein content. The results were (mcg / mL):
Tres Monjitas® 5.2 4.5 6.0 6.1 6.7 5.8
Suiza Dairy® 6.5 8.0 6.1 7.5 5.9 5.6
Mayagüez Dairy® 5.8 4.7 6.4 4.9 6.0 5.2
Indulac® 8.3 6.1 7.8 7.0 5.5 7.2
Using the method of ANOVA at a significance level of 0.05, test whether a difference exists between the average protein content of different brands of milk.