My 2 minute google search turned up nothing but it does make it harder to falsify a ledger if the sign is in front of the number. 200$ is the amount we agreed you'd pay me for that job. Here's your signed copy 1,200$. That being said some countries do place it at the end and at least one in the middle as the decimal point ex. 1.50$, $1.50, 1$50.
Speaking conventions vs writing conventions. There are lots of benefits to placing the currency sign before the amount in writing. It does- as others have said makes it harder to forge amounts- $100.00 can be changed to what? $100.009? So... you can get 1 cent if you round up? But 100.00$ can become 1,100$, 100,000,100.00$ etc.
But it also makes it easier to deal with. Say you have a form or contract? You place the “$” at the beginning and now they know the amount goes there after the symbol. Makes sense as in English we read left to right- having what the field is for AFTER the field would be confusing- especially when no other field is handled that way. Then there is formatting. If you have a box that holds... 10 digits? “$100 “ is easier to read and looks better than: “100 $”
In speaking- quantity comes before the noun. We say: “15 cows” not “cows 15.” We don’t have a widely used common symbol to denote when we are talking about cows, thumbtacks, shirts, people, burgers, cars, etc, etc. So we don’t see it written as “cars 20.” That said- the “$” is NOT the word dollars. It denotes the amount after it is dollars. “$50” is still pronounced “Fifty Dollars.” It’s just easier to write “$50” than “50 dollars” on something that comes up commonly and in business/finance etc. you’ll often see many dollar sums within the same document.
So even though the SYMBOL comes before the number- the “$” doesn’t mean “dollars” it means- “this number is a dollar amount...” So writing: “10$” isn’t “10 dollars” it is “10 and no dollars.” The “$” doesn’t=“dollars.”
>>one hundred( 1 100 )
*language is weird
200$ ~200,200$
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