I recently wondered about what portion of the world's population can take a derivative.
It is like a statistic: world literacy. (Then leftist Americans wonder: how many wonen.... )
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Leibniz and Newton, some 400 years ago, figured out how to describe a changing slope.
In the 1600s, they were only two guys. Then several. Nowadays, how many people can take a derivative?
I reckon that 5% (1 in 20) of the world's population can take a derivative.
Of course, many more can read this text - billions.