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What do you do when you've got a mathematical expression that's unsolvable because the numbers you need don't exist? You do what Hero of Alexandria did: you just invent one. That's how we got the concept of imaginary numbers, which Rene Descartes derided as being totally useless. Turns out he was wrong. #shorts

Where would we be with this dot?! It doesn't seem like much, but it's a critical element to our quick understanding of numbers. Without a decimal point or radix point, we have to mentally solve a little puzzle to figure out what the numbers we see actually mean. But with it, we know exactly what numbers we're looking at, and we know it instantly. And thanks to the printing press, we got rid of the line that just... wasn't very good at communicating what we needed to know. Decimals!

Just because you see a number like 100,000 doesn't mean it's actually 100,000. We operate in a base-10 numeral system, and it's got the familiar 10-based decimal root -- and "decimal" even comes from the Greek "deca" prefix meaning 10. But... not everyone thinks of the world in tens. Mainland Europeans used dozens, the Chinese and Mayans and Cherokee used the vigesimal base-20 system, and remnants of the sexagesimal base-60 system is what gives us 60 minutes and 360 degrees in a circle. There are lots and lots of ways to count and express number, and the simple system we have today is a beautiful conglomerate of thousands of years of experimentation.

Original Title: Greed, Lies, and Math: Busting America's Richest Woman