Low-fat or low-carb? Are low-fat diets or low-carb diets moreeffective for
weight loss? A sample of 77 subjects went on a low-carbohydratediet for six
months. At the end of that time, the sample mean weight loss was4.7 kilograms
with a sample standard deviation of 7.16 kilograms. A second sampleof 79
subjects went on a low-fat diet. Their sample mean weight loss was2.6 kilograms
with a standard deviation of 5.90 kilograms. Can you conclude thatthe mean
weight loss differs between the two diets? Use α = 0.01.
a) State the hypotheses.
b) Compute the test statistic, t.
c) How many degrees of freedom are there (simple method)?
d) Do you reject H0? Give a concluding statement.
