This is designed with the abacus and the notes available, the present invention relates to the abacus of simple structure, easy to carry and use.; According to the present invention, the main plate body which is the main plate seen are arranged to enable the abacus; And it is fixed to one side of the main plate body so as to be adjacent to the arrangement surface of the main plate seen, that the memory area is exposed to the outside of a white board; a main plate including a is provided.
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