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How to sort out primary school mathematics as a whole
Question 1: Is the proportion written in units?

In traditional textbooks, the ratio in primary school is defined as "the division of two numbers is also called the ratio of two numbers, and the quotient of the former divided by the latter is called the ratio, and the ratio is also called the ratio", which indicates the multiple relationship between two quantities, so the ratio has no unit. The ratio has no unit when representing the same kind of ratio; When the ratio of different kinds of quantities is expressed, the ratio can be expressed in units. For example, it takes about 2 hours to run 36 kilometers, and the ratio of distance to time is about 18 1, and the ratio is 18. This ratio means running 18 km/h, and the unit behind it is km/h, so it is expressed in units. That is to say, due to the expansion of the concept of ratio, when two different quantities are compared, a new quantity will be produced. This new quantity is the ratio of two different quantities, which is a unit quantity. Because the concept of ratio is extended to the comparison of different kinds of quantities, the meaning of ratio tends to be interpreted in a broader sense accordingly. If the teacher takes whether there is a ratio unit as the learning content and integrates it into the teaching of related content properly, then students will not doubt or contradict the ratio of different kinds of quantities after entering middle school. But whether it is called or not, the teacher should understand that the ratio of similar quantity is a ratio, and there is no unit; The ratio of different kinds of quantities is a unit quantity.

Question 2: Can all integers with denominator 1 be regarded as false scores?

Analysis: There is a judgment question on page 48 of the fifth grade exercise book of primary school mathematics: integers can be regarded as false scores with denominator of 1. Let's take a look at the definition of false fraction: as opposed to true fraction, the fraction with numerator greater than or equal to denominator is called false fraction. That is, the false scores are all greater than or equal to 1. Look at the sentence "Integer can be regarded as a false fraction with denominator of 1". "Integer" also contains 0, as the denominator of the numerator obviously less than 1. So this sentence is wrong. This question examines the meaning of false fraction, and it should be clear that only 0 in all natural numbers can not be regarded as a false fraction with denominator of 1 All nonzero natural numbers can be regarded as false fractions with denominator 1

Question 3:101-102 =1. How to move the number of 1 to make the equation hold?

Analysis: The solution to this problem depends on a good sense of numbers and good computing ability. Considering the difference of this subtraction formula, only the number 1 cannot be moved obviously. The minuend moves any number smaller than the minuend, and the minuend is equal to the subtraction of the minuend, that is, 100, 102 can reduce the movement by 2 to the upper right corner, and the square of 10 is equal to 100. Through this problem, we can see that primary school mathematics teaching should pay attention to the cultivation of students' sense of number, and the cultivation of sense of number depends on keen observation ability. Observation is a lasting perceptual activity with a purpose, a plan and positive thinking, and it is the gateway to thinking. Any mathematical problem contains certain mathematical conditions and relationships. In order to solve the problem, it is necessary to observe the problem thoroughly and carefully according to its specific characteristics, and then carefully analyze it, and examine its essence through superficial phenomena, so as to have a sensitive feeling, feeling and perception of the problem and make a quick and accurate response.

Question 4: How to pronounce negative numbers in primary schools?

Analysis: Students begin to recognize negative numbers in the second stage of compulsory education. The specific goal of mathematics curriculum standard is: "to understand the meaning of negative numbers in familiar life situations, and to use negative numbers to represent some problems in daily life." The teaching of negative numbers used to be arranged in middle schools, but now it is arranged in this unit mainly because negative numbers are widely used in life. Students have come into contact with some negative numbers in their daily life and have a preliminary understanding of negative numbers. On this basis, the preliminary understanding of negative numbers can further enrich students' understanding of the concept of logarithm, which is conducive to the convergence of mathematics in primary and secondary schools and lays a good foundation for further understanding the meaning and operation of rational numbers in the third period. Therefore, the significance of negative numbers in life and how to read and write negative numbers in a standardized way are also very important in primary school. Reading method: add "negative" before reading, and writing method: add "-"before the written numbers. It should be noted that the reading method of negative numbers should not be confused with its meaning, and students need to pay special attention to it. For example: -3 floor, pronounced -3 floor, means 3 floors underground.

Question 5: What are the ways to write time?

Analysis: The way of expressing time in primary schools can be expressed in hours, minutes and seconds, or in the form of electronic watches. What needs attention here is to distinguish whether the time mentioned is "elapsed time" or "moment". Time represents the time at a certain point. For example, a train arrives at Beijing Station at 2: 30 pm, which is the time when the train arrives. Time is the length of time. For example, a train leaves Shanghai Station at 7: 30 in the morning and arrives at Beijing Station at 15: 30. Then, the train time from Shanghai to Beijing is 8 hours, that is, from 7: 30 to 15: 30, that is, 8 hours. There are two ways to express time, namely hours, minutes, seconds, and electronic watches. The elapsed time can only be expressed in hours, minutes and seconds. In fact, the difference between these two concepts is well expressed literally in Chinese: time means a certain moment (fixed node), while time means the interval from the beginning to the end.

Question 6: Are scores divided into true scores, false scores and scored scores?

Analysis: The principles to be followed in classification should be considered, and the classified objects are neither repeated nor omitted. One criterion of score classification is "the relationship between score and 1". There are two types: less than 1 and greater than 1. That is, true points and false points. This standard has covered all possible scores. Obviously, scores cannot be classified into another category. It is greater than 1, which is related to the false score. If the division is hard, the objects will be duplicated. Scores are divided into two categories (true scores and false scores), and with scores is just another representation of false scores.