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Problem Statement:


Find a map of a continent with many countries. Color the map so that no two bordering countries are the same color. What is the fewest number of colors needed to completely color a complicated map? Explain your answer.

Problem setup:


I thought that South America would be one of the easiest continents to use.


Plans to Solve/Investigate the Problem:


I printed an outline map of this continent in order to color it for experimentation.


Investigation/Exploration of the Problem:


After experimenting with orange, yellow, and green, I realized that I needed another color because three would not be enough. So, I tried blue. Then I had a second thought that if I re-colored, I may be able to use just three colors. So, I went over the original ones with a different color just using green, yellow and blue—omitting orange. After several trials, I discovered that I could not use only three colors. So, I went back to using four and that is the smallest number of colors that I found one could use in coloring South America.


Pam Joseph