How Did the Romans Calculate? | blog@CACM | Communications of the ACM
Abacus - Wikipedia
Abacus - Wikipedia
Abakus (Rechenhilfsmittel) – Wikipedia
File:Soroban (Abacus).JPG - Wikipedia
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File:Noe abacus.jpg - Wikimedia Commons
This portable 1st abacus would have been particularly useful for Roman engineers, merchants, and tax collectors. Columns can calculate fractions and single units on the right side, all the way up to