Th e National Public Health Service for Wales reports that 33% of all Welsh adults have at least one chronic condition. Suppose you live in a county where the environment is conducive to good health and low stress and you believe the conditions in your county promote good health. To investigate this theory, you conduct a random telephone survey of 20 adults in your county.

a. On the basis of the fi gure from the National Public Health Service for Wales, what is the expected number of adults in your survey who have a chronic condition?

b. Suppose only one person in your survey has a chronic condition. What is the probability of getting one or fewer people with a chronic condition in a sample of 20 if 33% of the adult population has a health problem? What do you conclude about your state from the sample data?