Keywords: elementary school grade three operational mathematics

This article is suitable for: the third grade of primary school.

Composition source:

This composition is about 500 words in the third grade of primary school. The topic is "Mathematical Operation of Substitution Method". Everyone is welcome to contribute enthusiastically.

Method of substitution's mathematical operation seems simple, but it is not easy to do it without mastering the skills. When I was doing this kind of problem, I was stumped from the beginning. I have been thinking hard for a long time, but I still can't figure it out. Finally, I consulted my father, who explained it to me for a long time before I understood.

Things are different now, and I am already familiar with this kind of problem. The skill of doing the problem is two words: "substitution". Let me tell you something. For example, the questions are □\u△= 4, □-△=24, and ask □ =? ,△=? .

The method is as follows: from □\u△= 4, we can know that □=4×△. Substitute □=4×△ into □-△=24, and you get 4×△-△=24, that is, 3×△=24, then △ equals 24÷3, then △ = 8, and □ equals 4×△=32. Simple! This is the replacement method.

It's just a question. If you want to master method of substitution skillfully, you have to practice more. If you do more, practice makes perfect. If you do a difficult problem, Zhang Fei eats bean sprouts-a piece of cake.