| Math Logic |
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|
| Question : |
| What
is 'Four-Colour' problem ? |
Answer : |
| About the middle
of the 19th century, this problem known as the Four
Colour problem related to map making was proposed and remains
unsolved to this date. |
| Problem : |
 |
| The problem involves the colouring of
maps using at most four colours. When two countries have common
boundries, they must have different colours. When two countries
have only single points in common they may use the same colour. |
| No one, so far, has been able to produce a map
that would require more than four colours. But no one has been able to prove
that four colours are sufficient for all maps. |
|
However, it has been proved that if a map could be drawn that would require five colours, there would have been at least
36 countries on it. And it has also been proved that five colours are sufficient for all maps, but may not be necessary. |
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This theory was first proposed in 1852 when Francis Guthrie,
while trying to color the map of counties of England, noticed that only four different colors were needed.
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