I will say though that I prefer the way you normalize fuel consumption, as distance per units of fuel (miles per gallon), compared to our way of fuel volume per 100 distance units (liters per 100km).
I'm not super smart (nor do I in anyway claim to be) but people often consider me to be smart when really it's all down to two things, I think about things other people don't consider and I have endless curiosity about almost everything, I'm an eternal 5 year old constantly asking why.
They "did research" which found that a handful of people didn't understand fractions, in an unusual group social setting which can easily amplify oddball beliefs if other participants aren't 100% confident.
You can do general polling of a question like this, which will give you actual serious data about whether Americans understand fractions.
Right.
>> not because Americans are too dumb to understand fractions.
Wrong. They did research and found that to be a significant factor.
I'm sure there's /some people/ who don't understand fractions, but the vast majority of people I've met understand fractions and use them in their daily life...
That's what I thought years ago when I first heard about this, but you might need to get out into other parts of the world. I see at least 2 kinds of people who will make the mistake 1) People with no math ability (these really do exist) and 2) People who could easily see the difference if they thought about it even a little bit, but 3 vs 4 is smaller at first glance and they never bothered to "think" about it. There are a lot of the second kind of people too. Advertising doesn't usually need people to think, in fact they usually don't want you to do that.