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The so-called abacus mental arithmetic is abacus mental arithmetic. Abacus calculation is a calculation method that uses abacus as a tool to perform operations such as addition, subtraction, multiplication, division and square root. There are certain rules and formulas in the skill of transporting beads. When the user can skillfully operate the abacus, he can not only get the correct answer quickly, but also describe the disk type, grade and floating change of the abacus in his mind. This vivid abacus image is called "virtual disk". It completes abacus calculation in the brain through the process of perception, image and memory, which is what we call abacus mental calculation.