A study reports the mean change in HDL (high-density lipoprotein, or "good" cholesterol) of adults eating raw garlic six days a
week for six months. The margin of error for a 95% confidence interval is given as plus or minus 7 milligrams per deciliter of blood (mg/dl). This means tha:_________a) There is a 95% probability that the true population mean is within 7 mg/dl. b) The study used a method that gives a results within 7 mg/dl of the truth about the population in 95% of all samples. c) 95% percent of the population has changed their HDL after eating raw garlic six days a week for six months. d) We can be certain that the study results is within 7 mg/dl of the truth about the population. e) We could be certain that the study result is within 7 mg/dl of the truth about the population if the conditions for inferences were satisfied.
The margin of error describes how many percentage points the results will differ from the real population value, thus 'the margin of error for a 95% confidence interval is given as plus or minus 7 milligrams per deciliter of blood (mg/dl)' can be interpreted as 'The study used a method that gives a results within 7 mg/dl of the truth about the population in 95% of all samples.'
