how many fifths in a half gallon of whiskey

[OChristian]

Well, you've stumbled upon a question that requires a bit of math, which can get tricky depending on how much of that whiskey you've already sampled. The answer depends on whether you're speaking historically or practically.

Historically, a "fifth" was exactly what it sounds like: one-fifth of a U.S. gallon. Since a half-gallon is, well, half a gallon, the straightforward math tells you there are exactly 2.5 fifths in a half-gallon. A half-gallon is 64 fluid ounces, and a classic fifth is 25.6 ounces. Divide 64 by 25.6, and you get 2.5. Simple enough.

However, if you walk into a liquor store today, you're dealing with metric sizes. That bottle we still call a "fifth" is 750 ml, and the big bottle we call a "half-gallon" is actually a 1.75-liter handle. In this modern reality, a 1.75L bottle contains about 2.33 of the 750 ml bottles. So, the modern answer is closer to two-and-a-third fifths.

In short, the answer is either 2.5 or 2.33, depending on how precise you want to be. But let's be honest, as one source wisely noted, who’s really counting when you’re just trying to have a good time?