Today, a group of children came to my house. As my brother, I must take care of them! It just so happens that my family has cookies with Want Want Gift Package, one * * *, and there are 33 cookies. There are four people at our door. I asked my cousin, "How many biscuits does everyone share?" Cousin can't remember at the moment. After a while, my cousin said, "Brother, each person is divided into 8 pieces, leaving one piece." I said, "That's right." But who is the remaining piece for? We are all willing to give it to our youngest sister.
Preview is a golden key.
The teacher arranged for us to preview division and estimation.
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.
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.
One time, the paper was issued, and it was a question of 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!
Two cars, A and B, both leave from AB. Car A travels at a speed of 56 kilometers per hour, and car B travels at a speed of 48 kilometers per hour. Every hour. The following is: the two cars meet at a distance of 32 kilometers from the midpoint. What's the distance between AB?
I have a question mark in my head today? Why do you only insert 10 candles on your birthday today? I am 1 1 years old! I am curious. I went to my mom, my dad and my sister, and they didn't tell me. Let me find the answer myself. I thought about it, and suddenly I thought of one year old, the age I imagined in my mind. I'm only one year old 10 years old. I told my mother, father and sister the answer, and they all said I was knowledgeable.
Today, my father, Uncle Zhang and I went to pay the toll. On the way, I am calculating the gas cost of the car and how much it costs every month. My father's car can hold 60 liters of fuel, one liter of 3 yuan, and fill it up once 180 yuan. Once every two weeks, once a day, it is estimated that 360 yuan is needed.
Today, when I was working in winter vacation homework, I found a question about true and false silver dollars, which read: A businessman has nine silver dollars, one of which is relatively light. Can you find a fake silver dollar with a balance? I thought and thought, but I still didn't get it. I have to ask dad. Dad said, "that lighter silver dollar must be fake." First of all, the silver dollars are divided into three groups according to three groups and put on the scale respectively. If the two groups are equally heavy, it means that these are real silver dollars. Then put the three silver dollars of the other group on the balance one by one. If the two are equally heavy, it means that the other is fake, that is, the lighter silver dollar. " I can finally tell Chu Zhen from Yuan Yin! I really admire my father. He is too clever. I will study hard and be as smart as my father.
A math problem
Today, I was stumped by a math problem. The question is this: "There are two bookcases in the school reading room. There are three times as many books in cabinet A as in cabinet B. Book lending in cabinet A 170, and book lending in cabinet B 10. At this time, the books left in the two cabinets are just equal. How many books are there in each cupboard? " After reading the question, I scratched my head and chin, but I couldn't think of a solution to the problem. Suddenly, my brother came. After reading the topic, he said, "This is a problem of difference times, mainly to find the difference times." After listening to it, I suddenly realized that I had listed the formulas at once.
2:
Today, my mother and I took 62 yuan to buy salad oil. On entering the supermarket, we saw salad oil. My mother took two barrels to pay. I quickly said to my mother, "No, the unit price of this barrel of salad oil is 32.5 yuan. In other words, the total price is 32.5×2=65 yuan, so we don't have enough money." Mom listened and said happily, "It's good to have you, otherwise I would have a problem."
3:
Mathematics in life
I am relieved that all the exams have been finished today. I sat in my seat and did nothing. I came across a book called Mathematical Genius in my desk by accident. Like a man who finds his way out in the desert, I am in high spirits. When I opened it, it was a portrait of Hua, and I found the "mathematical genius puzzle" according to the catalogue. I thought: Hua is not a detective. How can he solve the case? I read this article with questions. After reading it, I realized that the most important thing for Hua to solve this mystery is that he is good at mathematics and can calculate according to the numbers and symbols in mathematics. My wish is to be a detective like Sherlock Holmes. However, being a detective, like Hua, has a wealth of mathematical knowledge. Now, only by learning math well can I realize my wish.
4:
After the exam, I got 97 points. The highest math score in the class is 98.5. For the class, this score is high, but for me, this paper should be 100. If my "solution" is written, I can get 98 points. The last one is not that I can't do it, but that I am missing a number. I passed 100. Teacher, your comment last week was "Work hard!" . Teacher, you know, it is these two words that have added infinite strength to me and made me get a good score of 97 points. Here, I sincerely say "thank you!" " .
5:
This morning, my mother took me to the supermarket in Fallen. When I arrived at the store, I didn't know what to buy because of the dazzling array of goods. First, we came to the gourmet area. I chose Shanghaojia natural potato chips and Mengniu dried milk tablets, and my mother chose a bottle of vitamin chewable tablets for growth and happiness. Then we went to the electrical area and bought a Runxin repeater. Finally, we went to the daily necessities section and bought a San Xiao toothbrush. It was then that my mother remembered that she had only one hundred dollars with her, and I didn't know if it was enough. I looked at all the commodity prices: Shanghaojia natural potato chips 4.8 yuan, Mengniu fresh milk dried tablets 13 yuan, San Xiao toothbrush 3.5 yuan, growth-happy vitamin chewable tablets 29.9 yuan, Runxin repeater 62 yuan. Then I estimated that it would be 1 13 yuan. I quickly told my mother that there was not enough money. We'll put the Happy Growth Vitamin Chewable Tablets back. Fortunately, I learned to calculate this time, otherwise I would make a fool of myself!
6:
The smallest egg in the world
A few days ago in math class, the teacher gave us an application problem, saying that the largest bird egg in the world is ostrich egg, and its egg has 1300 grams. How much does the smallest egg weigh? I put a question mark in my mind. After surfing the Internet and reading books in various ways, I finally found the answer in the China Youth Encyclopedia: the smallest egg is a hummingbird egg, and the hummingbird mother lays 2~ 1 egg at a time, which is only the size of a bean, each weighing 0.5g About 200 hummingbird eggs are the size of an egg. Hummingbirds can fly out of the nest for food and start an independent outdoor life after living for about 20 days. What interesting knowledge, it can not only learn, but also increase extracurricular knowledge. It really kills two birds with one stone.
7:
My revised edition
I often get 100 in math exams. Other students asked me if I had any tricks. I told them that I had a "correction book", which helped me a lot. In the past, when handing out exercise books or test papers, I only looked at the grades or scores given by the teachers, and never considered what was wrong, why it was wrong, and how to correct it. As a result, every time I make a mistake here or there, I can't get full marks. Once, my math teacher said to me, "We should really learn knowledge when we learn knowledge, and we can't just look at grades and scores. If the question is wrong, carefully analyze the cause of the mistake. I suggest that each of you prepare a correction book, copy down the types of wrong questions, find out the reasons for the mistakes, and seriously correct them. " From then on, I prepared a small notebook, only the size of the palm of my hand, and wrote three words on it, "Correct the wrong book". Whenever exercise books and test papers are handed out, I always analyze them carefully, copy the wrong questions on the "correction book", carefully analyze the reasons for the mistakes, mark the mistakes with a red pen and correct them carefully. For example, when I was learning to solve equations, it was recorded in my "error correction book". The cause of the error in topic analysis was corrected to x-16 =18 =18+16 = 34. This is a writing format error, which is affected by the calculation format outside the table. Every step of solving the equation is necessary, and the equal signs should be aligned. X-16 =18x =18+06x = 3416x = 4x = 4, where x is a factor, we need to divide the product (4) by another factor (16), because 16x = 4x = 4 ÷16x = 0.2523-2x = 32x = 23+32x = 26x =13 Here is the subtraction of the known difference and the minuend. The difference should be subtracted from the minuend, and the difference added by the minuend in this problem is not equal to subtraction. 23-2x=3 2x=23-3 2x=20 x= 10 When I am free, I always take out my beloved "error correction book", read it carefully and keep my homework in mind. This is the secret that I often get 100 points.
8:
Uncover the mystery of the tea cone
Recently, we are learning three-dimensional graphics. This caused me to think about the problem that most tea cones are cylindrical. Why? Is it polite or beautiful to make the tea cone cylindrical? Or ... no, no. I don't understand! Wondering, I made up my mind to solve this mystery. Today, there came an uncle at home who I admired since I was a child. His name is Zhuge Liang. I picked up the tea cone and prepared to make tea for him. Suddenly I had a brainwave and asked him, Uncle, do you know why most tea cones are cylindrical? My uncle asked me, "Tell me first, why?" ? I don't want my uncle to look down on me. I really want to find the right answer with what I have learned. As time went by, I was sweating with anxiety, but I couldn't find the answer. At this time, my uncle patted me on the shoulder and said to me, you might as well start with a figure with the same circumference and a larger circular area, and then consider it. After listening to my uncle's words, it suddenly dawned on me that using a cylindrical tea tube can not only hold more tea leaves, but also save materials. Knowing this, I combined real life and painting to prove my idea. I told my uncle this idea, and my uncle gently stroked my head and said, "You are good at finding math problems from real life and trying to solve them." I believe you will be the future' Zhuge Liang'.
9:
Life is inseparable from mathematics.
I used to think that learning to find the least common multiple was boring. It's really annoying to deal with the problem of finding the least common multiple of 1 1 and 12 all day. I have always felt that it is useless to learn this knowledge in my life. However, one thing changed my view. That was not long ago. Grandpa and I went to the Youth Palace by bus. My father and I took the No.3 bus and were about to leave when the 1 bus just took us away. At this moment, grandpa looked at two cars and suddenly smiled and said to me, Xiao Ying, grandpa has a question for you, okay? I am confident to answer: good! Then listen carefully, if the 1 bus runs every 3 minutes and the No.3 bus runs every 5 minutes. How many minutes will it take for these two cars to start at the same time? After a pause, I said, Grandpa, you can't solve this problem. Grandpa looked at me doubtfully: Oh, really? There is still one condition missing in this problem: 1 bus and bus No.3 start at the same place. After listening to my words, grandpa suddenly patted his clever bald head and said with a smile: I, a' doctor of mathematics', sometimes get confused. My questions are not rigorous enough, but I will still think seriously. Grandpa and I laughed happily. Then grandpa said, well, now suppose it's the same starting point. What method do you use to answer? I thought about it and blurted out: 15 minutes again. Because 3 and 5 are prime numbers, finding the least common multiple of prime numbers is equal to the product of these two numbers (3х5= 15), so 15 is their least common multiple. In other words, two cars can leave at the same time in at least 15 minutes. Grandpa praised me: correct answer! 100 integral. Yeah! After listening to grandpa's words, I raised my hands happily. From this incident, I understand a truth: mathematical knowledge is really everywhere in real life.
10:
How long is this straight line?
Tonight, my cousin and I are playing on the playground. We found a square waste paper board with an area of about one square meter near the playground. My cousin looked at it and said, "Xiao Jing, if you divide this cardboard into small squares with an area of one square millimeter, and then connect these small squares one by one into a straight line, how long is this straight line?" I blurted out without thinking, "How long can this last? Four meters at most! " Cousin smiled and said, "Don't jump to conclusions yet, let's work it out together." I straightened my back and began to think for a while: 1 square meter equals100000 square decimeter, and the side length of a square with 1000000 square millimeter is 1000000 mm, so isn't it the same with 1000000 mm? Wow! This straight line, which consists of some small squares of one square millimeter, is as long as 100 meter. At this point, I understand that learning mathematics can't be easily concluded just by looking at the topic. You have to think carefully and calculate carefully before you can do it right and explore the mystery.
1 1:
This morning, the teacher gave out the math exercise books. I looked at it and said, "What happened to an application problem?" I said in surprise. A closer look reveals that one step of conversion is missing. I thought it over. How many kilometers should 20400 meters be equal to? 20400÷ 1000=20.4 (km) Oh, it turned out to be 20.4 km, so I filled it in and gave it to the teacher for approval. The teacher looked at it and said, "The unit of 340×60 should be meters, not kilometers." I looked at it, and it turned out that the units in the above formula were wrong. I changed it again, and this has just been approved by the teacher. Today is the first time I have approved it for the teacher twice. I used to be able to approve it once. I think we can give teachers a batch of good students at a time, so I used to be an upper-middle class in Shi Yang.
12:
Today is Sunday. My mother opened my exercise book and looked at it. "God, how can you make so many mistakes?" My mother turned over as she spoke, only to see her face getting redder and redder and looking very hot. I glanced at her face, her voice was a little rough, and said, "Can't you know any of these questions?" I shook my head, and my mother's face turned redder. At this time, my mother took out the draft paper from her bag, brushed it with a pencil and wrote two formulas: 0.76 ton = () kg 2.85 kg = () kg () g. My mother asked me how to do these two questions: the answer to the first question was 760 kg, and the answer to the second question was 2 kg 850 g. My mother asked me what I thought. I thought about it and said, "If the unit is large, multiply it by the forward speed. If the unit is small, divide it by the forward speed. " . At this time, mom's anger is gone.
12:
Do you believe in yourself or others? If I choose, I must believe in myself, and there is only one thing to prove. Once, the teacher gave out a math workbook to practice, and a classmate came to see my workbook. He said I made mistakes together, but I don't believe him. I just won't change. No matter how I explain it, he just won't listen to me, and then we shouldn't listen. At first I wanted to change, but I controlled myself and insisted that I was right. The next day, the teacher handed out the exercise book. I found that I was right. I am very excited. I'm confident that I'm right, even if I'm wrong, but it's worth it, because I didn't peek at others.