Final answer:
The median age of the U.S. population was around forty years old in 2010, indicating that the population is aging with about half being younger and half older than that age.
Step-by-step explanation:
The median age of the U.S. population is a statistic that represents the midpoint of the population's age range. According to the U.S. Census Bureau in 2010, the median age is approximately forty years old. This means that about half of the individuals in the United States are younger than forty, and about half are older. As the median age has been on the rise, it indicates that the overall population is aging. Additionally, the U.S. older adult population is categorized into three subgroups: the young-old, the middle-old, and the old-old, showing a range of aging experiences.