According to a recent poll, 28% of adults in a certain area have nigh levels of
ID: 3230628 • Letter: A
Question
According to a recent poll, 28% of adults in a certain area have nigh levels of cholesterol. They report that such elevated levels "could be financially devastating to the regions healthcare system" and are a major concern to health insurance providers. According to recent studies, cholesterol levels in healthy adults from the area average about 209 mg/dL, with a standard deviation of about 20 mg/dL, and are roughly Normally distributed. If the cholesterol levels of a sample of 50 healthy adults from the region is taken, answer parts (a) through (d), (a) What shape will the sampling distribution of the mean have? The sampling distribution of the mean is skewed right. The sampling distribution of the mean is skewed left. The sampling distribution of the mean is normal. There is not enough information to determine the shape of the sampling distribution. (b) What is the mean of the sampling distribution? mu = 209 mg/dL (c) What is the standard deviation? SD(y) = mg/dL (Round to two decimal places as needed.)Explanation / Answer
a) Since Population standard deviation is known
we can use normal distribution
Hence option C is correct
b) Mean of sampling distribution is E(x) =Mu=209
c) Standard error =sigms/sqrt(n) =20/sqrt(50) = 2.8284