Just for interest - some thoughts on 'three score' and 'quatre-vingts'.
Historically, there is more than one method for counting. There is the method that us Anglophones know, which comes from the Romans and is called base ten. This means that everything is based on multiples of ten.
In French too, we see this, up until the seventies when, as we've said, things go weird. Then in comes the "vigesimal system" which used the base 20, hence quatre-vingt-quatre (84).
This is supposedly as they used their feet as well as their hands to count. Fingers and toes included, you get twenty.
Many believe it ended up in French due to the influence of the Celts in France, whose languages use the base 20 system. While others say it was the Viking influence and point to the fact that Danish numbers also works on the base 20 "vigesimal system".
One good example of this is the Paris hospital called “l'Hôpital des Quinze-Vingts” (The Hospital of fifteen-twenty). The hospital was so named because it housed 300 beds and 300 is 15 times 20.
And criticize as we might, the idea of counting in twenties actually used to be part of the English language too. Think back to Abraham Lincoln's famous Gettysburg address and you may remember how without realizing, we know ‘score' to mean twenty:
“Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty…”
To translate, ‘Four score and seven', means four, twenty and seven, in other words, 4x20 and 7; on exactly the same principle as the French!