Advanced Placement (AP) Human Geography Practice Exam

What aspect is highlighted by the rank-size rule regarding city populations?

1. All cities have equal populations

2. City populations grow uniformly

3. Population sizes relate to their rank in order

4. City sizes are determined by geographic location

The correct answer is: Population sizes relate to their rank in order

The rank-size rule illustrates that the population size of a city is inversely related to its rank within a hierarchical system of cities; specifically, it states that the population of a city is proportional to its rank in the urban hierarchy. For instance, if the largest city has a population of 1 million, the second largest would be approximately half that size, the third largest about one-third, and so forth. This pattern suggests a predictable distribution where the largest city predominantly serves as the economic and cultural hub, while subsequent cities offer diminishing size and influence. This concept provides insight into the organization of urban areas and can help geographers understand the distribution of resources and services within a region. Essentially, it conveys that larger cities tend to attract more people and resources, while smaller cities fill in the gaps in the urban system with their own specialized roles. Other options lack the nuance of the rank-size rule; for instance, the idea that all cities have equal populations overlooks the very premise of the rule, while the notion of uniform growth does not account for the variability in city sizes based on hierarchies. Lastly, ascribing city sizes solely to geographic location dismisses the critical factors of economic and social dynamics that contribute to urban growth and population distribution.