1、27÷3=?

2、30÷5=?

3、6×8=?

4、48÷8=?

5、54÷9=?

6、7×3=?

7、 18÷2=?

8、4×9=?

9、24÷4=?

10、36÷6=?

1 1、6×5=?

12、40÷8=?

13、9×7=?

14、27÷9=?

15、4×5=?

16、 15÷3=?

17、6×7=?

18、30÷6=?

19、8×4=?

20、20÷5=?

2 1、3×9=?

22、 16÷4=?

23、6×4=?

24、36÷6=?

25、7×2=?

26、24÷4=?

27、9×2=?

28、 18÷3=?

29、4×7=?

30、 12÷3=?

3 1、5×8=?

32、30÷5=?

33、9×5=?

34、20÷4=?

35、4×6=?

36、 10÷2=?

37、6×9=?

38、36÷9=?

39、29-5=?

40、38+5=?

4 1、43-8=?

42、20+8=?

43、34-6=?

44、 17+9=?

45、47-8=?

46、30+7=?

47、4 1-9=?

48、26+6=?

49、37-8=?

50、49+3=?

The method of oral calculation:

1. Mastering basic concepts: It is very important to understand and master basic concepts for any mathematical problem. In oral calculation, this includes the understanding of basic concepts such as numbers, digits, carry and abdication. Only by deeply understanding these concepts can we do oral calculations better.

2. Practice basic operation: The main purpose of oral calculation is to solve mathematical problems quickly and accurately. So you need to practice basic operations such as addition, subtraction, multiplication and division. You can improve the speed and accuracy of the operation through a lot of practice.

3. Use memory strategies: People can help to remember by various methods, such as converting numbers into images and using songs or rhythms. These methods can help children better remember numbers and operation rules, thus making oral calculations more convenient.

4. Decomposition of complex problems: For some complex mathematical problems, it is an effective strategy to decompose them into smaller and more easily solved parts. Breaking the problem into smaller parts can reduce the complexity of the problem, which makes it easier to do oral calculations.

5. approximation method: this method requires children to gradually approach the answer to the question, instead of trying to solve the whole problem at once. For example, when solving an addition problem, you can work out some numbers first, and then gradually approach the final answer.

6. Self-examination: Oral errors are inevitable, but they can be greatly reduced through self-examination. Self-examination includes repeating the questions, reviewing the calculation process, checking the calculation and other steps.