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Counterfeiting was a problem even in Medieval times.

A Medieval British Anti-Counterfeiting System: Split Tally Sticks

The cuts were made the full width of the stick so that, after splitting, the portion kept by the issuer (the stock) exactly matched the piece (the foil) given as a receipt. Each stick had to have the details of the transaction written on it, in ink, to make it a valid record.

 

 

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Why is a minute divided into 60 seconds, an hour into 60 minutes, yet there are only 24 hours in a day?

The Babylonians divided the day into 24 hours, each hour into 60 minutes, each minute into 60 seconds. This form of counting has survived for 4000 years.

The Babylonians had an advanced number system, in some ways more advanced than our present system. It was a positional system with base 60 rather than the base 10 of our present system. Now 10 has only two proper divisors, 2 and 5. However 60 has 10 proper divisors so many more numbers have a finite form.

For mathematical and arithmetical purposes they used the Sumerian sexagesimal system of numbers, which featured a useful device of so-called place-value notation that resembles the present-day decimal system. Measures of length, area, capacity, and weight, standardized earlier by the Sumerians, remained in use.