Comparing World Populations

We can use population size to compare different countries in our world.  One way to write large numbers such as population is in scientific notation.  Scientific notation is written as a decimal between 1 and 9 multiplied by a power of 10.
For example the population of Turkey is 79,749,000 people, or as 7.9749 * 10^7 in scientific notation.

The country of Mexico has a population of about 114,975,000 people, or 1.14975 X 10^8.  Mexico has approximately 35 million more people than Turkey.  

Another way to compare populations is to find out the population density.  The population density compares the population to the land area.   For example Turkey has a land area of 769,632 square kilometers. When we divide the population by the land area we find the population density.  The population density tells us how many people live per square kilometer of land.  In Turkey the population density is 79,749,000 people /  769,632 square kilometers = 104 people/square kilometer.  Mexico has about 1,943,945 square kilometers of land, and its population density is 59 people per square kilometer. So, even though the population is less in Turkey, it may feel more crowded because of a higher population density.

Population density is used to compare how crowded places are around the world.  The density of a place might suggest a good place to begin a business, or a good place to advertise a product/service.   Others may think that a place with low population density may be a more peaceful place to live with less noise or traffic congestion.  How do you feel, would you prefer to live in place with a high or low population density?

Use the websites below to explore places in the part of the world you live, or places that interest you.  Here are some questions to include as you explore as you compare world populations. 

• How do different cities or countries compare in population ? 
• How would the populations be expressed in Scientific Notation?
• How does the population density compare between the cities or countries?  

US Populations

World Populations

Illinois Facts

World Land Areas

Quiz on Population Density

Here's an example of a Density Chart

Country	Population (people)	Scientific Notation (Population)	Land Area (Square Kilometers)	Population Density Population ÷Land Area
United States	313,847,000	3.13847 X 10^8	9,161,966	34
Mexico	114,975,000	1.14975 X 10^8	1,943,945	59
Turkey	79,749,000	7.9749 X 10^7	769,632	104
Peru	29,550,000	2.9550 X 10^7	1,279,996	23

By looking at Density I learned about the ratio of people to land area.  It was interesting to me that Turkey had the highest population density of the four countries since Turkey had the second lowest population.
 I think that this high density may be caused by it's smaller land area.  Another thing I noticed was the lowest population density was from Peru who had just 32 people per square kilometer.  The population in Peru is therefore more spread out than the other countries which have a higher density than Turkey.

References

1. World By Map, http://world.bymap.org/LandArea.html, December 18, 2012
2. World By Map, http://world.bymap.org/Population.html, December 18, 2012