DIET SUPPLEMENTS Based on results from a random sample of 35 individuals, a company advertises that individuals who use its diet supplement lose an average of 4.6
pounds with a standard deviation of 1.2 pounds during the first week of dieting.
(a) A graph of the data reveals no strong skew or outliers. Does this provide evidence
of a significant weight loss?
(b) The advertisement fails to mention that these results were part of a double-blind
experiment to compare the supplement with a placebo. In the control group, the mean
weight loss was 3.7 pounds with a standard deviation of 2.3 pounds during the first
week of dieting. The control group consisted of a random sample of 32 individuals. A
graph of the data for the control group reveals no strong skew or outliers. Is there
evidence to show that the group taking the diet supplement lost more weight than the
control group in the first week?