Number and algebra is one of the four major sections of primary school mathematics, which mainly includes six contents: number cognition, number operation, common quantities, formulas and equations, ratio and proportion, and exploration of laws. The knowledge introduced in this chapter is compulsory for junior high school entrance examination.
There are many kinds of questions in the final exam of numbers and algebra, among which multiple-choice questions, fill-in-the-blank questions and calculation questions are common. Mastering the thinking and methods of solving multiple-choice questions and fill-in-the-blank questions is helpful to consolidate the knowledge of numbers and algebra, improve the efficiency of doing problems, and then improve the grades.
The textbook "New Mathematics Curriculum Standard" emphasizes that "number and algebra is one of the important contents of mathematics, and it is the basis and guarantee for students to learn graphics and geometry, statistics and probability, synthesis and practice. Mastering the knowledge of numbers and algebra will help students improve their computing ability, analytical ability and problem-solving ability. "
The important role of visible numbers and algebra in mathematics learning and examination. It is a necessary learning and examination skill for students to study various questions of number and algebra and improve their answering level.
Master the main points:
One is the model consciousness in quantitative relations. In specific cases, the common quantitative relationships are: total quantity = component+component, total price = unit price x quantity, distance = speed x time.
Among these common quantitative models, the first one belongs to addition model, and the other two belong to multiplication model. These two multiplication models are the relationship between total quantity and partial quantity, and the relationship between object quantity. Of course, the reverse operation of these models can be extended. However, in teaching, we still need to master the basic quantity of solid modeling.
The second is the transfer of number operation teaching. The teaching of number operation should use integer multiplication to understand the relationship between arithmetic and algorithm, and the inverse operation of multiplication leads to division; In addition, the range of numbers has expanded from integers to fractions (decimals), but in the process of this expansion, arithmetic and algorithms are all based on integer operations, and the algorithm is also applicable.
It can embody the important idea in mathematics, that is, "transformation", and form a preliminary sense of deduction in this process from "unknown" to "known".
The third is to establish a suitable actual situation. Whether it is the understanding, operation, quantitative relationship and estimation of numbers, it is necessary to construct a suitable mathematical life situation for students. During this situation, ask questions, ask questions, ask questions, ask questions.