[GilesB]

What is the exact blood alcohol content of “extremely drunk”?

[RegulatorCountry]

That varies by individual. A very heavy drinker with a high tolerance for alcohol could easily double the legal limit without having all that much external indication of being drunk. Someone who does not drink much at all could be quite tipsy at or below the legal limit.

[Steve_Seattle]

"What is the exact blood alcohol content of “extremely drunk”?"

There isn't one. It's like porn, you know it when you see it.