To calculate the population density of Phoenix, you divide the population by the area:
Population density = Population / Area
Using the given numbers:
Population = 1,445,632 people
Area = 450 square miles
Population density = 1,445,632 people / 450 square miles = 3,210.29 people per square mile (approximately).
Thus, the population density of Phoenix is about 3,210 people per square mile.