I really wouldn't assume those are mutually exclusive, based on my experience with survesy, but I agree that 20% is likely smaller than the actual number here. And 14% is an absolute lower bound which assumes that no one checked both "charge and pay off" and "pay cash", which is clearly an unrealistic assumption.

Even 14% is much higher than I would wish for answers to this sort of question, of course.

Anyway, if I had to read the tea leaves I would guess the "real" number is somewhere in the ~30% range based on EF5A and EF5B (EF5B was only asked if the respondent answered they would pay all bills in full for EF5A). That is, 22% of the respondents are having trouble paying existing bills in full (though what that means is another complex question, I bet) and another 11% (14% of 78%) would have trouble doing it if they had an unexpected $400 expense. That gets us to 33%; some of those might be able to recover from the $400 expense over the course of a month or three by temporarily running a small credit card balance and then paying it off, but it's not going to be too many I expect.

Which is pretty horrible. Not 47% horrible, but horrible.