Colours on the Globe

[Demongirlie]

I was looking at my world globe the other day and was wondering why the countries are all coloured different colours. Does anyone know why that is ???

[bernardo]

It is one way of preventing them being all the same colour.

[sddsddean]

It is just so you can differentiate one country from another. There are usually 5 colours used as this is the minimum amount you need to ensure you don't have two adjacent countries the same colour.

[bernardo]

It can be done with 4 colours.

[jake-the-peg]

Bernardo's brief reply hides the deep passions that have lain behind whether it was 4 or 5 colors required.

http://www.bbc.co.uk/radio4/science/another51.shtml

150 years ago this exchange between sddsddean and bernardo could have resulted in fisticuffs or worse! 

[Chapel]

They're actually that colour when viewed from space.

[jake-the-peg]

I know it took India years to rub out all that red when we left in 1948

[sddsddean]

I was always told 5, but thought 4 seemed more likely. However, every time I tried with 4 it never worked. Ah well, there you go.

[bernardo]

The 4-colour theory was proved in 1976.

[jake-the-peg]

Not so fast Bernardo!

It was demonstrated then with computer assistance - I don't think it has been proved inductively yet.

[bernardo]

"Not so fast"?  29 years is not very fast in my book.  It has been proved anyway.

[tullett]

i think its coz different countries belong to different countries belong to different empires, like the us owns hawaii even though there native language sounds nothing like english