According tothe Gallup poll 27 of US adults have high levels

According tothe Gallup poll, 27% of U.S. adults have high levels of cholesterol. They report that such elevated levels \"could be financially devastating to the U.S. healthcare system\" and are a major concern to health insurance providers. According to recent studies, cholesterol levels in healthy U.S. adults average about 215mg/dL with a standard deviatino of about 30mg/dL and are roughly Normally distributed. If the cholesterol levels of a sample of 42 healthy U.S. adults is taken,

A) What shape should the sampling distribution of the mean have?

B) What would the mean of the sampling distribution be?

C)What would it\'s standard deviation be?

D) If the sampling size were increased to 100, how would your answers to part a-c change?

Solution

According tothe Gallup poll, 27% of U.S. adults have high levels of cholesterol. They report that such elevated levels \"could be financially devastating to the U.S. healthcare system\" and are a major concern to health insurance providers. According to recent studies, cholesterol levels in healthy U.S. adults average about 215mg/dL with a standard deviatino of about 30mg/dL and are roughly Normally distributed. If the cholesterol levels of a sample of 42 healthy U.S. adults is taken,

The sample size is 42 which is greater than 30. There fore shape of the sampling distribution of the mean is approximately normal.

Mean =215mg/dL

C)What would it\'s standard deviation be?

Sd of sampling distribution = 30/sqrt(42) =4.629

D) If the sampling size were increased to 100, how would your answers to part a-c change?

If we increase the sample size to 100, the sampling distribution of the mean is approximately normal.

Mean =215mg/dL

Sd of sampling distribution = 30/sqrt(100) =3.0