Now that's just confusing!

Of course Decimal is not Hex, and Hex is not Decimal.

They are different, but they are just different ways of representing the same thing.

A number can be represented in Decimal notation or Hexadecimal notation or Binary notation, or Roman Numerals or whatever you like. The notations are different, but they are just different ways of representing the same number.

For an example, see http://www.8052.com/forum/read.phtml?id=65390

It's just like different languages have different words for a chair - the object remains the same, even though different people use different words to describe it in different languages.