| 摘要 |
For teaching young children counting and other operations, a counting frame is used with a rod bent into a U shape along which balls can slide from one leg to the other. The rod is connected to a base frame by hinged connections so that it can be swung from a vertical to a horizontal position. The base frame has an end partition with grooves into which the two legs fit when horizontal, supporting it. Between this partition and the hinged end are further intermediate partitions, forming zones along the rod, to hold selected numbers of balls. ADVANTAGE - Adding, subtracting and multiplication can be readily learnt.
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