It’s the school’s fault. They say so. But not here: most information designers create junk charts when using areas. In 7th grade kids learn how it is right and wrong. It makes them competent with media.
Teachers have their book with solutions. On page 81 it says:
left: essentially a column chart – one car symbol represents 10,000 cars; reasonable
right: length and height increase by 66%; perception is distorted, because the area is doubled
Now, I wish more competent media to all kids competent with media.