Provide you with four articles! (1) Mathematics impressed me deeply. Math, I love you just as mice love rice. Do you know why I like math? Because of the charm of mathematics, it attracted me deeply. I learned a new knowledge today, which is a simple addition and subtraction algorithm. After learning the simple addition and subtraction algorithm, my calculation speed is much faster and it is easier to learn to calculate. Give an example! For example: 367+498=? I just have to think like this: add up 498 to make 500, and then use 367+500. I found that I added 2 more, so I subtracted 2 from the total to get 865. And 796+295? I think so: 796 can be added to 800, 295 can be added to 300, one plus 4 and one plus 5, then the formula becomes 800+300-4-5= 109 1. Look, how convenient it is! After learning the simple algorithm of addition, learning the simple algorithm of subtraction will be much easier. Such as: 483-299, hehe, you can find the way by gently moving your head. I'll take 299 and subtract it from 300, because it's 1, so just add 1 to the result, which is 483-300+ 1= 184, and the calculation is much simpler. However, I can warn you: it's best not to think about the minuend when doing subtraction, or you'll be in trouble! Now, I like math more and more, because it makes me learn to calculate the results quickly, and math really makes me remember deeply! (2) Preview is the golden key. After math class today, the teacher arranged for us to preview division and estimation. What is a preview? Why does the teacher want us to preview? I came home with a surprise. Check the information and ask your parents. It turns out that preview is to read the contents of the book by yourself before learning a new lesson. Mark what you don't understand, and then listen carefully in class. ) In this way, you can have a preliminary understanding of new knowledge. I previewed the division estimation curiously. Through preview, I know that when estimating 538÷62, 538 can be regarded as 540 and 62 as 60, so 538÷62≈9. It turns out that preview can help me clear away the obstacles in math learning and have a preliminary understanding of estimation. Can quickly accept new knowledge in class. Even if there is doubt, it can be easily solved. Therefore, it is very important to preview before class, so we must develop the good habit of preview, because successful preview can make the lecture quality higher and the learning efficiency higher, so it is the golden key to open the door to knowledge. The annual math contest began. The forest is very lively. This year's contestants are: cotton seed, turtle, tiger and lion. The game has already started. Teacher Swan first gave each of these candidates a test paper, and then said to them, "Whoever can calculate correctly and quickly in a certain period of time will win the Wisdom Cup Award." As soon as Mr. Swan finished. These candidates began to write. Rabbits run fast and do fast. I saw that she was very clever and soon finished more than half of it. Come on, let's have a look at its test paper. "dizzy! ! ! "You see: 80-70= 150, 20 ÷ 4 = 80 ... What a mess! I didn't even see the operation symbols clearly. Look at the lion and the tiger. Hey! Why don't you see lions and tigers? I only saw a lot of manuscripts. Before I left, I saw lions and tigers busy! It turns out that every time a lion does something, he has to take out the manuscript paper to calculate. The more manuscripts are piled up, the more lion heads are hidden. Really simple-minded, developed limbs. Tigers are more exaggerated. Every time I finish a question, I will take out my manuscript and check it. No wonder you are sweating. Finally, let's look at the tortoise! The tortoise is usually slow-tempered, but this time its thinking is not slow at all. See how wonderful this question is: 3456-999 = 3456-1000+1= 2457. The tortoise uses a simple algorithm to finish the test paper quickly, and it is right and fast! Finally, the tortoise won the wisdom prize. (4) the importance of 0 0 is a mysterious number, as elusive as the mystery in the universe. 0 is also an important number. If you accidentally add an extra 0 or a less 0, the consequences are really unimaginable. This math exam really made me realize the importance of 0. It was 99 points when the test paper was handed out! I made a mistake at once. The result made me dumbfounded. The result is 4500÷90. "How could I make a mistake with such a simple question?" I muttered to myself. I remember that when I dictated the 45,000-90 question, I easily wrote down 50, and I was still very confident. But in the end, I got 500, which was a 0. How wrong it is! What should not be wrong is also wrong. How important 0 must be! If I become the financial general manager of the company in the future and someone else comes to withdraw money, I would have taken 10000 yuan, but I added 0- 100000 yuan more, and I still put 10000 yuan on the bill. Then who should I ask for this 90 thousand yuan? I will bear all the consequences!