The source for the original article from NY times this quote was taken from is Taubman's autobiography.
https://www.amazon.com/dp/B000RO9VM2
The exact quote is this :
Well, it turned out that customers preferred the taste of our fresh beef over traditional fast-food hockey pucks. Hands down, we had a better product. But there was a serious problem. More than half of the participants in the Yankelovich focus groups questioned the price of our burger. "Why," they asked, "should we pay the same amount for a third of a pound of meat as we do for a quarter-pound of meat at McDonald's? You're overcharging us." Honestly. People thought a third of a pound was less than a quarter of a pound. After all, three is less than four!
There's no other source, data or anything besides the CEO's word that his massive marketing scheme was definitely not his fault and it was obviously just because americans are too stupid to do math.
It's possible folks back then were bad at math, but it's far more likely Taubman was passing blame, as is the tradition of CEO's everywhere since the beginning of time.
Well, this reply is buried, but the TIL is sourced from a book written by a former A&W franchisee who hired Yankelovich, Skelly and White, a well-known marketing research firm to figure out why they weren't selling. The relevant passage from the book:
> Well, it turned out that customers preferred the taste of our fresh beef over traditional fast-food hockey pucks. Hands down, we had a better product. But there was a serious problem. More than half of the participants in the Yankelovich focus groups questioned the price of our burger. "Why," they asked, "should we pay the same amount for a third of a pound of meat as we do for a quarter-pound of meat at McDonald's? You're overcharging us." Honestly. People thought a third of a pound was less than a quarter of a pound. After all, three is less than four!
A&W eventually renamed their burger since the 1/3 pound label confused people.
I'm sorry, but this seems to be an instance of "If you repeat it enough times, it becomes true." This was posted four years ago on Reddit, from a Mental Floss article which is now a dead link citing something two years prior. There is no original source. There is no snopes verdict one way or the other.
The only source to the source which is just a fucking quote is from a 2014 Mother Jones article, citing the biography of A. Alfred Taubman, "Threshold Resistance." It was never independently verified.
This is most likely a bunch of horseshit.