(a) A special diet was given to 16 children and their gain in weight was recorded over a 3-month period. Their mean gain in weight was found to be 2.49 kg. A control group consisting of 16 children of similar background and physique had normal meals during the same period and gained 2.05 kg on average. Assume that the standard deviation for weight gains is .8 kg. Is the evidence strong enough for us to assert that the special diet really promotes weight gain?
(b) Answer the question in (a) if each of the two groups consisted of 50 children.