Abacus is a tool for calculating Since the early days of the calculator includes a rectangular frame. The core of the abacus round. For the count You can scroll up and down Abacus mechanical model like this has many different forms. And several regions such as the Babylonian, Roman, Chinese, Japanese, but the best known is the Chinese abacus. Abacus provides a mathematical model based on imagination. Which will be on line with only one child

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