What A and B or C means does it mean AandB or C or A and BorC?

Answer 1

I think those two operations are equivalent. You can chose whichever you want.

Meaning : Let's attribute to A, B and C the truth values 1 1 and 0. The first choice ends like this : 1 and 1 = 1, 1 and 0 = 1. Now with the second, 1 or 0 = 1, 1 and 1 = 1. Although this is only an example, feel free to judge the 8 possibilities!

It's a little easier in mathematics using parentheses, etc. The bottom line is that the phrase is badly in need of re-writing, because even if there is a technically correct way to interpret it, there will often be confusion with this kind of construction. One general rule: Group the items reconciling all the 'nots', then all the 'ands', then all the 'ors'. So without any other clues to help, I would interpret the above to mean: (A and B) or C. Of course the important thing is the intention of the writer. So we're back to the editing room. However, the questioner put this item in the 'Writing' category, so it deals more with language than with math or logic. If I asked "Do you want bacon and eggs or oatmeal?" there is little or no ambiguity. If I asked you "Do you want Filet Mignon and Green Beans or Asparagus?" there seems also to be little or no ambiguity. How about "Do you want red and green or blue?" "Do you want pencils and oils or pastels?" "Do you want classical and jazz or blues?". In these cases it would be far better to ask or write: What colors do you want? What art supplies do you need? What kinds of music do you prefer?