Suppose we want to compare fasting serum-cholesterol levels among recent Chinese immigrants to Ghana with typical levels found in the general Ghanaian population. Suppose we assume cholesterol levels in women ages 21−40 in Ghana are approximately normally distributed with mean 190 mg/dL. It is unknown whether cholesterol levels among recent Chinese immigrants are higher or lower than those in the general Ghanaian population. Let’s assume that levels among recent female Chinese immigrants are normally distributed with unknown mean μ. Hence we wish to test the null hypothesis H0: μ = μo = 190 vs. the alternative hypothesis H1: μ ≠ μo. Blood tests are performed on 100 female Chinese immigrants ages 21−40, and the mean level (x) is 181.52 mg/dL with standard deviation = 40 mg/dL. What can we conclude on the basis of this evidence?
The cholesterol level of Chinese immigrants is lower than those in the general Ghanaian population