A Zone diet is one with a 40%–30%–30% distribution of carbohydrate, protein, and fat, respectively, and is based on the book Enter the Zone. In a study conducted by researchers Christopher Gardner and associates, 79 subjects were administered the Zone diet. After 12 months, the mean weight loss was 1.6 kg, with a standard deviation of 5.4 kg.
Do these results suggest that the weight loss was statistically signiﬁcantly greater than zero at the 0.05 level of signiﬁcance? Do you believe the weight loss has any practical signiﬁcance? Why?