What is population density, and how is it calculated?

Population density is defined as the number of people living per unit of area, commonly measured in people per square kilometer. This metric is calculated by taking the total population of a specific area and dividing it by the total area in square kilometers.

Understanding population density is important as it provides insights into how crowded or sparse a region may be, affecting various factors such as resource allocation, urban planning, and infrastructure development.

The other options do not correctly define or calculate population density. The total area in square kilometers alone does not provide a measure of how many people reside within that area. The ratio of urban to rural population refers to demographic distribution rather than density itself. The population growth rate per year focuses on changes in population size over time, not density. Thus, the first option accurately captures the essence of what population density represents.