Mental Arithmetic is a method of computation through "visualization of abacus" to achieve the result of computing.

“珠心算”是一种利用“脑中算盘”，达成运算目的的心算方法。

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At some stage documents with numbers, and even long-term aspirations, will become necessary again, and the nation that invented the abacus will have to overcome its aversion to arithmetic.

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