Three-number straight-adding and straight-subtracting abacus with three beads on each upper

Abstract

The invention discloses an upper-three type three-number direct-adding and direct-deducting counting frame. The traditional counting frame has more calculation formulae which are complex to learn and difficult to understand; besides, the traditional counting frame can not realize direct adding or deducting and can be hardly combined with the written calculation of the modern mathematics education, so the studying function is difficult to be embodied. To solve the problems, the invention makes improvement on the traditional counting frame and provides a upper-three type three-number direct-adding and direct-deducting counting frame; the counting frame changes the two upper beads of the traditional type counting frame into three beads, and the five lower beads into twelve lower beads, and becomes a type counting frame; wherein, each upper bead stands for 5, while each lower bead stands for 1. The counting frame can further become a type or type counting frame. The counting frame needs no formula in the calculation and is easy to learn and understand; as long as the user can count and dial the numbers, the user can directly add or deduct numbers through the counting frame; the counting frame combines with the written calculation of the modern mathematics education and can have a better understanding and awareness into the concept of carry and borrow.

Description

technical field [0001] The invention relates to a teaching aid, in particular to an abacus. Background technique [0002] Abacus is a traditional Chinese calculation tool and an important invention in ancient China. The use of abacus and abacus is not only convenient for calculation, but also has the effect of exercising thinking ability. Using the abacus requires the close cooperation of the brain, eyes, and hands. Therefore, many schools and parents use the abacus to train children's thinking and calculation skills. Traditional abacus generally adopts the bead structure of "up two down five", "up two down four", "up down five" or "up down four". The calculation of this kind of abacus requires a separate set of formulas: [0003] Addition table [0004] Add one: one to one, one to five to four, one to nine to one; [0005] Add two: two to two, two to five to three, two to eight to one; [0006] Add three: three to three, three to five to two, three to seven to one; ...

AI Technical Summary

Problems solved by technology

[0023] There are so many formulas, and there are 2 to 3 situations for each addition or subtraction of a number, it is more complicated to learn and difficult to understand

This set of formulas is only applicable to the traditional abacus, and cannot be used in other places. It is easy to forget after a long time. It can only be used on the premise of memorizing the formulas. During the calculation, follow the formulas to dial the beads. The problem is that it is impossible to achieve direct addition and subtraction, and it is difficult to combine with the written calculation of modern mathematics education, and the current teaching does not encourage students to learn mathematics by reciting and memorizing.

The traditional abacus is manufactured and used as a calculation tool. With the appearance of the calculator, the calculation function of the abacus is rarely used. It is more used as a tool for learning mathematics. The traditional abacus needs to follow the formula to dial the beads. Learning function is difficult to reflect

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