100, math diary's 400-word article, an excellent fourth-grade primary school student, is a mysterious number, as elusive as a 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. It turned out to be 4500? 90 this question. ? How could I make a mistake with such a simple question? I muttered to myself. Remember when I was calculating 45,000? I easily wrote 50 out of 90 questions, and I was still confident, but in the end I got 500, which was 0 short. How wrong it is! What should not be wrong is also wrong. How important 0 must be!
If I became the financial general manager of the company in the future and someone else came to withdraw money, I would have taken 10000, but I added 0 100000 more, and I still put 10000 on the bill. Then who should I ask for this 90 thousand yuan? I will bear all the consequences!
Through this incident, I understand that I should be meticulous in my work and study, otherwise the consequences will be very serious.
Comment on a math exam, the author can find the wrong reasons for the wrong questions, think deeply and reflect, so as to appreciate them? 0? The importance of, and thus lead to a serious attitude towards future work, at an early age can have such insight, is commendable.
Math diary, an excellent fourth-grade pupil, has 400 words. 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. How careless! 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.
Comments: Students can vividly reproduce the problems in the process of answering questions in very humorous language. Four kinds of animals represent four kinds of students, some are sloppy, some are diligent and some have no brains. I hope readers can learn from it!
Today is Sunday. When I am writing my math homework, will you do it? Try your hand? I saw two calculation problems, namely: 3? 999+3+8? 99+8+ 10? 99+ 10+2? 9999+2=? And 333? 334+222? 999=? . I've been doing it for a while, but I still can't. I quickly asked my mother to teach me. My mother came to have a look and said that these two questions can be applied to the multiplication algorithm you have learned. What multiplication algorithms have you learned? I replied: multiplicative commutative law, multiplicative associative law, multiplicative distribution rate. ? Mother nodded with satisfaction and patiently explained to me.
Mom said:? 3? 999+3=3? 999+3? 1=3? (999+ 1)=3? 1000=3000, and the multiplication distribution rate is used here. Do the math yourself. I thought about it and said excitedly, I do! I will! 8? 99+8=8? 99+8? 1=8? (99+ 1)=8? 100=800; 10? 99+ 10= 10? 99+ 10? 1= 10? (99+ 1)= 10? 100= 1000; 2? 9999+2=2? 9999+2? 1=2? (9999+ 1)=2? 10000=20000; Finally, add up to get the final number, that is, 3000+800+1000+20000 = 24800. ? Mother nodded with satisfaction and said, not bad, my son is really high! ?
The second question was prompted by my mother. She said: 999=333? 3. Think about what you should do. I still don't know how to do it. Mom said again: Actually, 333? 334+222? 999=333? 334+222? 333? 3=333? 334+333? (222? 3)=333? 334+333? 666? Then I suddenly realized that it was like this, so I went on to say: equal to 333? (334+666)=333? 1000=333000? . I thought it was funny, so I burst out laughing.