Advanced Placement (AP) Human Geography Practice Exam

What does the rank-size rule suggest about the population of cities?

1. Each city's population is equal

2. The second largest city has about 1/2 the population of the largest city

3. Population is confined to urban areas only

4. Population density is uniform across all cities

The correct answer is: The second largest city has about 1/2 the population of the largest city

The rank-size rule provides a model that describes the relationship between the size of a city and its population. According to this rule, the population of a city is inversely proportional to its rank in the hierarchy of cities within a certain area. Specifically, if the largest city has a certain population, the second largest city is expected to have about half that population, the third largest about a third, and so on. This creates a predictable pattern in size distribution, where the population of cities can be estimated based on their ranks. Thus, the rank-size rule demonstrates how urban areas distribute their population, suggesting that as you move down the hierarchy of cities, the population decreases in a specific proportionate manner. This rule often holds true in many developed countries, where the largest city is significantly larger than the others, and subsequent cities decrease in size in accordance to their rank.