What is the maximum number of colors necessary to color a map on a plane?

What is the maximum number of colors necessary to color a map on a plane? A.) swuare root of n rounded up, where n is th enumber of countries on the map B.) four C.) n/4 rounded up, where n is the number of countries on the map D.) This can only be determined using a computer model of the map. Explain your answer.What is the maximum number of colors necessary to color a map on a plane?There are a couple of flaws in your question.



1. It doesn't specify any conditions.

It is customary to say "such that no two adjacent countries are the same color".



2. It should ask for the minimum.



The maximum is the same as the number of countries

(assuming each country is colored with 1 color - otherwise there is no maximum at all.)



For the minimum,

the famous Four Color Theorem states:

You need at least four colors to color all the countries on a planar map such that no two adjacent countries use the same color.



So the intended answer is no doubt B) four.