# elementary statistics

posted by .

The distribution of cholesterol levels in teenage boys is approximately normal with u=170 and o=30. Levels above 200 warrent attention. Find the probability that boy has a cholesterol level greater than 225.

• elementary statistics -

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion Related to the Z score you calculate.

• elementary statistics -

how many seven digit telephone numbers are possible if digits can be repeated?

## Similar Questions

1. ### statistics

Cholesterol levels of adult males are approximately normally distributed with a mean of mg/dL and a listed standard deviation of . Some researchers claim that the standard deviation of cholesterol levels of adult males is less than …
2. ### statistics

Cholesterol levels of adult males are approximately normally distributed with a mean of mg/dL and a listed standard deviation of . Some researchers claim that the standard deviation of cholesterol levels of adult males is less than …
3. ### statistics

Experts consider high serum cholesterol levels to be associated with an increased incidence of coronary heart disease .suppose that the logarithm of cholesterol levels for males in a given age bracket are normally distributed with …
4. ### Statistics

Cholesterol levels of adult males are approximately normally distributed with a mean of mg/dL and a listed variance of . Some researchers claim that the variance of cholesterol levels of adult males is less than . Suppose that we want …
5. ### Statistics

The serum cholesterol levels in men aged 18 to 24 are normally distributed with a mean of 178.1 and a standard deviation of 40.7. A group of 9 men aged 18 to 24 randomly selected. 1. Find the probability that there are at least 2 men …
6. ### statistics

mean cholesterol is 175mg/dl..standard deviation =20mg/dl assume approx normal distribution ..is varied. what percentage has a cholesterol level above 155mg/dl?
7. ### statistics

The cholesterol levels of young women aged 20 to 34 vary approximately normal with mean 185 milligrams per deciliter and standard deviation 39 mg/dl. Cholesterol levels for men vary with mean 222mg/dl and standard deviation 37 mg/dl …
8. ### Statistics

The distribution of cholesterol levels of the residents of a state closely follows the normal curve. Investigators want to test whether the mean cholesterol level of the residents is 200 mg/dL or lower. A simple random sample of 12 …
9. ### statistics

The following table shows the summary statistic of the cholesterol levels of two groups of men in 2014. From 25 to 40 years old, the mean is 224, standard deviation is 5.5 and the sample size is 12. From 41 to 55 years old, the mean …
10. ### statistics

The cholesterol levels of adult American women has a mound-shaped and symmetric distribution with a mean of 188mg/dL and a standard deviation of 24 mg/dL. In what interval would you expect most American womenâ€™s cholesterol levels …

More Similar Questions