Selected methods of mental arithmetic and their application in everyday life

This pre-scientific work examines selected methods of mental arithmetic and their applicability in everyday life. Strategies for beginners and advanced learners are presented, including calculation tricks for basic arithmetic operations, Trachtenberg's two-finger system and a method based on memorizing complementary numbers. The aim is to evaluate the practicality of these methods and demonstrate their usefulness in various everyday situations.Another focus is on the importance of mental arithmetic in the education system. Current teaching practice is analyzed on the basis of the Austrian curriculum and interviews with two experienced mathematics teachers. This is supplemented by a comparison with Chinese mathematics lessons and an interview with a Chinese teacher. The work concludes with considerations on how the mental arithmetic skills of pupils can be sustainably improved.