figures. you're blonde... jk.

The saying "couldn't care less" is redundant. You are trying to say that you don't care but by saying "could not" you ate also saying that you do care and do not want to lower the level of caring. The proper way to say that you should care less is " could care less" meaning that your level of caring could in fact be lowered. People misuse the saying and OP was trying to not have to correct themselves because they are smart

33- It's likely an example of people mishearing something and repeating it, like using units of mass and calling it weight.

39- I'm not entirely sure if you're a troll or not but I'm just going to say that you have it backwards. If you "could care less", there is an implied level of caring. If you "couldn't care less", there is no level of caring, therefore it cannot be lowered, hence people say they couldn't care less about things that, frankly, they don't care about.

Wee said!

Let me clear this up, as "could care less" is my BIGGEST PET PEEVE. Saying "could care less" implies that to some extent, you care, because you could care even less than you do now. "Could not care less" is the proper phrase, meaning you do not care at all, so you literally could not care any less.

39, repeat exactly what you just explained, except backwards, and you'll actually be correct. (i. e., "I couldn't care less" is the correct format because you are saying that you could not possibly care any less than you do)