In this short and funny talk, Terry Moore gives the surprising answer.
https://www.ted.com/talks/terry_moore_why_is_x_the_unknown?
I find some good articles about math
What Is Algebra?
By Robert Coolman March 26, 2015
Keeping Time: Why 60 Minutes?
Keeping Time: Time Zones, Trains and the 24-Hour Day
https://www.livescience.com/author/robert-coolman
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