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History of Abacus. By: Huy Do & Trinh Huynh. Outline. History of abacus Abacus lingo Why use abacus How to add How to subtract How to multiply How to divide. History of Abacus. Abacus ? (personal calculator) - a device used for “+”, “-”, “x”, “/”
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History of Abacus By: Huy Do & Trinh Huynh
Outline • History of abacus • Abacus lingo • Why use abacus • How to add • How to subtract • How to multiply • How to divide
History of Abacus • Abacus ? (personal calculator) - a device used for “+”, “-”, “x”, “/” - does not require the use of pen & paper and good for any base number system - derives from the Greek word ABAX – table or board covered with dust • Most historians believe the abacus was first created in Central Asia • From there it spreads West to Europe, and East to China, and its neighboring Oriental countries • “Modern” Chinese abacus - appeared in China between the 12th and 13th century AD.
“Modern” Chinese abacus lingo 13 12 11 10 9 8 7 6 5 4 3 2 1
Why use Abacus? • Run by hand • Simple to use • Operate for years • Teach you how to manipulate numbers - how each digit relates to the others and use that knowledge to do all the major operations - +,*,/ • Let you learn all about the base ten system • Show you how to math in the decimal system and the binary system • Can solve problems just as fast or even faster than a modern electric computer.
How does it work? • The first column is for units • The second column is for tens • The third column is for hundreds • And so on…