| 摘要 |
PROBLEM TO BE SOLVED: To provide an arithmetic training implement enabling easy understanding of interrelation, etc., between addition and subtraction. SOLUTION: The arithmetic training implement is composed of a rectangular base plate 2 and an annular slide band 3, slidably looped around the base plate between the both sides 2a, whose width is smaller than the shorter side of the base plate. The peripheral surface of the slide band is divided into two sections-a first and a second quantity indication sections A, B. The remaining section of the base plate which is not covered by the slide band serves as a third quantity indication section C.
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