In a recent study, 10 272 moderately obese subjects were randomly assigned to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted calorie; or low-carbohydrate, non-restricted- calorie. The prediction was that subjects on a low- carbohydrate diet would lose weight, on the average. After two years, the mean weight loss was 5.5 kg for the 109 subjects in the low carbohydrate group with a standard deviation of 7.0kg. The MINITAB output shows results of a significance test for testing H0: μ = 0 against Ha: μ ‰  0, where μ is the population means weight change. Weight change is determined by calculating after weight - before weight.

a. Identify the P-value for this test.
b. How is the P-value interpreted?
c. Would the P-value and 95% confidence interval lead to the same conclusion about H0? Explain.

SE N Mean StDev Mean 95% CI 109-5.500 7.000 0.670 (-6.829,-4.171) -8.20 0.000