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Summary

DescriptionAbacus Base Five Ten.PNG	This is the small abacus of Al-Khwārizmī abacus with base-five/ten. All upper beans have the five values, and all down beans has the ten values. Hypothetically, this kind of abacus was used on the paleography of modern numerals. It is assumed to have originated because humans have ten fingers.
Date	born around 780 and died around 850
Source	http://en.wikipedia.org/wiki/Muhammad_ibn_Musa_al-Khwarizmi
Author	Al-Khwārizmī

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