Now I'm confused. The article says at one point that ANSI "letter" is 8 1/2 inches by 12 2/3 inches and also that "letter" size is 8 1/2 inches by 11 inches wit

Now I'm confused. The article says at one point that ANSI "letter" is 8 1/2 inches by 12 2/3 inches and also that "letter" size is 8 1/2 inches by 11 inches without explaining the discrepancy. So which is it?