From the article: “24 million babies will someday be President.” This seems an improbable claim. Is he saying something sensible by virtue of the surrounding analysis that I’m just not following?
The parsing is ambiguous, read it with parentheses as follows:
1 in (6 times 4.0 million = 24 million) babies will someday be President
Yeah, I think it's a typo and should have been "one in every 24 million babies" - this makes sense given the numbers, with 4 million born every year but only a new president every 6 years.