Population density is a numerical measure of the relationship between the number of people and some other unit of interest expressed as a ratio called - total number of people divided by the total land area.

Arithmetic density.

Explanation:

It is also called the real density and is a measured by the total number of people divided by the total land area.  While the population density is the measurement of the population per unit of area or unit volume and is frequently used to a living organism and is a key variable to measure of the population characteristics and pattern.