Age of U.S. Residents. The U.S. Census Bureau collects information about the ages of people in the United States. Results are published in Current Population Reports.

a. Identify the variable and population under consideration.

b. A sample of six U.S. residents yielded the following data on ages (in years). Determine the median of these age data. Decide whether this descriptive measure is a parameter or a statistic, and use statistical notation to express the result.

29 54 9 45 51 7

c. By consulting the most recent census data, we found that the median age of all U.S. residents is 37.2 years. Decide whether that descriptive measure is a parameter or a statistic, and use statistical notation to express the result.