The mean total cholesterol for a population of men between the ages of 20 and 29 is 180 micrograms per decilitre with a standard deviation of 37.4. A healthy total cholesterol level is less than 200, 200-240 is border line, and above 240 is dangerous. Assume the distribution is approximately Normal. For a randomly selected man from this group, what is the probability that his total cholesterol level is
200 or more?
Between 200 and 240?
On a standardized test, scores are normally distributed with a mean of 400 and a standard deviation of 80. What score must one have to be in the 80th percentile?