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Abacus for mechanical and visual counting of uprising, has cord enclosing uprisings, where abacus is placed in square plate with preset uprisings around zero point so that multiplication can be represented within small range
Abacus for mechanical and visual counting of uprising, has cord enclosing uprisings, where abacus is placed in square plate with preset uprisings around zero point so that multiplication can be represented within small range
The abacus has uprisings (2) and a cord (3) that encloses the uprisings or a part of the uprisings. The abacus is placed in a square plate with 10x10 uprisings around a zero point (6), so that multiplication can be represented within a range as small as 1x1. The zero point is attached with appropriate line up number starting with 1. The cord is fastened in a mounting hole of an end piece (4) that is in the form of a ball or cube.
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