In official documents, numbers are first written in arabic numerals, and then they are immediately written out with words. This is to make certain no fraud can be made. (I assume.) What is the correct way of doing this? The two forms have to be linked with a word, don't they?
Example: "$1234... one thousand two hundred thirty four dollars"
In place of the dots, should you write "that is,"? (Putting a comma between the arabic numerals and "that", like so: "$1234, that is, one thousand two hundred thirty four dollars".)
Should I just put the written-out variant in parenthesis?
Example: "$1234 (one thousand two hundred thirty four dollars)"
I hope my question is clear. :)
*If a separate rule is valid in non-official documents, please be so kind as to explain that as well.