1, many senior three students are prone to make low-level mistakes and simple calculation mistakes when doing mental arithmetic in exams. It's easy to blame the mistake on carelessness.
2. Because children have developed mental arithmetic problems, they are always used to thinking in their heads. This habit of thinking only without writing is fatal to learning mathematics. Mathematics is a discipline that pays attention to strict logical reasoning, especially in junior and senior grades, which requires the calculation of equation functions. Even a genius who learns to dominate can't solve it without writing. Many seemingly complicated problems, as long as you write and simply calculate two steps, you will find ideas.