[Abacus input mode is newly supported. ]
It is a collection of calculation problems for practicing addition and subtraction (addition, subtraction) using the abacus.
Questions are asked in a format called profitability. Add or subtract the numbers displayed on the screen in order from the top to calculate the total of all the numbers.
It is possible to ask and answer questions about adding and subtracting numbers from 1 to 13 digits. Customize the problem to your level.
It can also be used as a test preparation because it can answer questions in a format similar to the abacus ability test currently being conducted in Japan.
* Only the problems of addition and subtraction are supported. Multiplication and division problems are not included in this app.
* This app is positioned as a training app that uses an abacus, but it can also be used for mental arithmetic calculations that do not use an abacus.