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Chinese abacus is known as the 5th invention of Ancient China.
You use it to teach children simple mathematics.
It can be used to obtain square roots and cubic roots.
The abacus can perfom addition.
The abacus was created in China.
Cheng Dawei is worshipped as the 'god of Arithmetics'.
Numbers are added by grouping beads together on wires.
It helps you memorize multiplication tables.