Math diary, fourth grade.

A busy and full day has passed. There must be some interesting stories around you on this day. Why don't you keep a diary now? So what problems should we pay attention to when writing a diary? The following is the fourth grade math diary I compiled for you. I hope it will help you.

Math diary, Grade Four 1 This summer vacation, my mother took me to Hong Kong Disneyland. Compared with the mainland, Hong Kong is very small, with a population of about 6.6 million, with a total area of 1070 square kilometers. The smallest Disneyland in the world is located on Hong Kong Island, with an area of only 65,438+026 hectares (365,438+00 acres). The tour guide said, "If you don't play anything, just walk around for 18 minutes." Let me show you my trip to Disney!

First, we went to Mickey's photo studio and took photos with Mickey and Minnie. When we got there, we saw: Wow! There was a long queue in front of the photo studio, almost 25 meters long. My mother tried her best to take me in. Finally, we went to the Cinderella carousel to play. I got on the merry-go-round and took a closer look. The turntable has three circles, and each circle has 15. I calculated: 15× 3 = 45 (1). Wow, so many! We turned round and round on it, feeling like a happy scene when riding a horse on the grassland. I was deeply impressed by the following fantasy space trip, adventure world, mini world, the performance of the lion king and the Mickey Mouse award party.

Things in Disney are very, very expensive. A bottle of Coke 17 yuan is more than ten yuan more expensive than ours. At lunch, a bowl of noodles 50 yuan. Have you ever eaten a bowl of noodles for 50 yuan? It's really expensive! Before we leave Disney, everyone wants to buy some souvenirs. My mother bought me an umbrella for Princess Disney, which cost 100 Hong Kong dollars. On second thought, we only need 20 yuan for each umbrella here, 100÷20 = 5 (one umbrella). Wow! This is too expensive!

When I got on the bus and left Disney, my mother asked me, "How long did we play from 8 am to 6: 30 pm today?" I thought about it: 6: 30 pm is 18: 30, 18: 30 -8: 00 = 10: 30.

The bus started, and I reluctantly bid farewell to Disney Park: Goodbye, we will come again next time!

Math diary, a senior, stayed at home this winter vacation because of the epidemic. One day, my mother said, "Let's play a game with our brains. As long as you name two numbers casually, I can immediately calculate their sum and subtract their difference. "

I'm a little skeptical. I asked, "Any number will do?" Mom said, "Yes, of course!" So, I thought about two numbers and said to my mother, "452 and 637, can you immediately tell the sum of 452+637 minus the difference of 637-452?" Mom immediately replied, "It's 904. "I was still a little skeptical, so I quickly took a pen and calculated it vertically. The result was the same as my mother said. I thought to myself, I must be too small, and it is difficult for my mother to make two bigger bodies. I was a little unconvinced and said, "9734 and 6420, you can't figure it out now, can you?" "12840, it must be right!" Mom said confidently. I calculated it vertically again, and the answer is the same! Now, I have nothing to say and have to admire my mother. I said, "Mom, you must have some secret, otherwise it wouldn't be so fast. Please tell me quickly! " Mom said, "I'll give you three questions." After you finish, look for the rules and see if you can find the secret. " So, I started this problem seriously.

①26 and15: (26+15)-(26-15) = 30.

②637 and 200: (637+200)-(637-200) = 400.

③3 186 and1040: (3186+1040)-(3186-1040) = 2080.

After working out the answer, I observed it carefully for a while and said happily to my mother, "I see, the final figure is twice as small." It's also true that my mother asked me to look up some questions myself.

Then, my mother asked, "Do you know why the number is twice as big as the smaller number?" I shook my head to show that I didn't know. So, my mother said, "We can use letters to represent any number, or we can write such a deduction process (A+B)-(A-B) = A+B-A+B = B+B = 2B. Learn more math knowledge in senior three, and you will understand this secret more deeply. "

After listening to it, I suddenly realized. It turns out that there are so many mysteries hidden in a small number, and I think mathematics is really interesting.

One day in math diary's fourth grade, a teacher wanted to test his students' math. So, he said in a math class, "I will give each of you a piece of paper and write any four numbers on it." I dare say that the difference between the two numbers written by everyone can be evenly divided by three! " "The students didn't believe it, so the teacher sent a piece of paper. After a while, everyone wrote.

When the students read and write the good numbers one by one, the teacher can find two numbers divisible by 3 on a business trip. No one is an exception! For example: 1963, 1765, 1736, 1376 ... The difference between the two numbers can be divisible by 3. What's going on here? It is found that when any natural number is divided by 3, there are only three possibilities for the remainder, namely, the remainder 0, 1 and 2. If natural numbers are classified according to the remainder after division by 3, they can only be divided into three categories.

And the teacher asked the students to write four numbers, so there must be two numbers with the same remainder. Subtract two numbers with the same remainder (reduce the large number), and the difference can of course be divisible by 3! After the students knew it, they cast an admiring look at the teacher. Students, don't you want to have a try?

Location: Symbol Kingdom

Characters; =、÷、×、+、-、()

My name equals a number. Look how neat my two braids are!

My name is organization. Although I am not very good-looking, I am very useful!

X: My name is multiplication sign. I don't look right, but don't write me wrong!

+:My name is the plus sign. I look like ten years old, but I'm not ten years old, so I want to make it clear!

-:My name is minus, just like one. How beautiful and neat!

One day, the symbol girl was noisy in the symbol kingdom.

Book: I'll give you 1 questions. Take your positions. The topic is this:

3333=6

The symbols are all standing, there is nothing wrong!

(): It's a good thing it's not as ugly as the slogan, otherwise we'll become ugly ducklings when our neat queue is in a mess.

Hearing (), the ship bowed its head.

● Are my two black balls so annoying?

Book:+How can you say that? We are all good friends and must help each other!

The symbols were ashamed and let Yan join them again. Children, do you know how they are combined?

Math diary, a senior, remembers a math class, and the teacher gave us an interesting lesson. Although the course is only 40 minutes, we feel as if we have just started. Why do you feel this way? Because teacher Wang's teaching is very interesting, we can't wait to come to math class on Saturday and Sunday.

The teacher came into the classroom with a big smile on her face. "Hello, classmates." We said, "Hello, teacher." Please sit down. The teacher said, "Today, let's review Unit 3: Understanding of Angle and Triangle." Teacher Wang led us to review the measurement of angles, the drawing of angles, the classification of triangles, and the relative size of angles ... When the teacher talked about the degree of the sum of internal angles of triangles, the students said in unison, "The sum of internal angles of triangles is 180." The teacher smiled happily, but at this moment, Mr. Wang pretended to be fine and called his classmates over and asked, "Triangle." "180" The teacher then drew a big triangle and a small triangle on the blackboard and asked, "Whose inner angle is bigger than theirs?" "Big Triangle" students immediately raised their hands. If they stand on the podium, their hands will look like a small forest! "XXX, you say!" "It should be the same size." "Yes, XXX, did you hear that?" The teacher went to the table in the third row in the south and said, "Turn to page X of the textbook and look at question X." The book drew a big triangle and divided it into two small triangles on average. "The sum of the internal angles of the big triangle is 180. What is the sum of the internal angles of one of the small triangles? " The students say "90" and "wrong" together. They say "I don't know" and "Alas ... the teacher called me!" The students can't sit still. XX said, "Miss Wang is so accurate, why can't she do anything?" "Teacher Wang is really something." Teacher Wang found another classmate. The classmate said, "90" and we sighed, "360" and "I don't know" ... At this moment, a small forest came out. The teacher laughed again and again, and so did the students. The teacher also called my deskmate "180" and answered loudly. "Alas," the students sighed again. First, they didn't call themselves. Second, they finally found the opportunity to meet.

Everyone was just about to continue the class when the bell rang and the students "Ah!" This will be more! ""class is over so soon, isn't it? " Teacher Wang said, "Yes, the bell rang. Class is over! " "Stand up" "Hello, teacher! Ha ... no, the teacher is resting! " Teacher Wang smiled knowingly and left.

We are looking forward to the next interesting math class, which I will never forget!

Fourth grade math diary 5 integer fraction decimal prime compound positive and negative function derivative high Austrian number! I hate gnashing my teeth at the thought of it.

Since the first grade, the subject I hate most is mathematics. For example, what is 100 million, you can see at a glance, there are only a handful, and there are so many zeros; What "π" can't be eliminated, so it's troublesome to calculate; What is the common multiple common factor? How can I make it clear? Ah, Aquinas! Forcing me to find a classmate to divide short; I really can't draw fan-shaped, bar-shaped and broken-line statistical charts well. Alas, I can't even give a grid for this question. Hey, I feel dizzy when I see this algebra and geometry. What the hell is science? It's boring and annoying. I'd better learn Chinese.

None of the above is the most important. The most important thing is that I am always careless, so the problems that I could have done and the problems that I can't do are deducted together, which leads to my math performance standing out in the class. Decimal low marks are endless for me, and countless bright red forks have shattered my fragile mind. Woo-hoo, I have long been disappointed with my math scores. Mathematics is the most important thing in school now! My scar!

No, recently, I finished the math problem with a sad face, but I was lazy and didn't have a clear conscience. As a result, as soon as the homework was given, all the questions that I was dumbfounded at once were crossed out. Huh? What happened? I looked at the question of survival and became confused. Suddenly, my eyes went black, and I found myself making a serious mistake, that is carelessness. It's all wrong I was not like this before. My eyes were bloodshot, and a hatred came to my mind: "Math, you humiliated me, you discouraged me!" " ! I hate you! I hate you! "I am very unhappy, and I immediately threw my exercise book back. I swear I will never listen to math class again! Just wasting time. It's better not to study hard than to make mistakes, and you can save some dignity when you die. What's the use of sweating again It will be wrong anyway. Isn't this a waste of energy and time?

However, after I scolded, I couldn't help running to the table to do math problems, and I couldn't help but maintain a high degree of enthusiasm in math class. Hey! I really hate math, I hate it, but I hate it less than I love it after all!

Math diary, in the fourth grade, has mathematics everywhere in her life. For example, how many steps are there when we go upstairs and downstairs? How many light bulbs are there in the house? How long will it take us to eat ... Today, I want to know what we can do in three minutes.

After getting up in the morning, I began to wash my face and brush my teeth. My mother got up much earlier than me, and now she is hanging clothes. I felt a little bored, so I picked up my watch and began to time my mother to see if she could dry the clothes in a few minutes. After a while, I pressed the stopwatch and saw that it was exactly three minutes. When my mother saw me timing, she said angrily, "What's the use of timing here?" Think about how long it will take you to do things! "My mother said," It only takes me three seconds to open the door! """Think of something useful!" Mom said that and went to make breakfast. I sat down at my desk and thought about the time I needed to do. "I need 1 minute to make a verbal list; It takes 1 hour to read a book; It takes 10 minutes to wash the bowl once; Have breakfast ... ""Guo Songyuan, have breakfast! " Just thinking of having breakfast, my mother really wants me to eat it. I quickly ran to the table, picked up my watch and put it aside, ready to time again. After pressing the timer, I wolfed down the rice porridge in front of me and thought to myself, "How long will it take me to have breakfast?" I pressed the pause button on my watch and looked at the time-15 minutes and 23 seconds! "So I want to use'15 minutes and 23 seconds' for breakfast!" I muttered to myself. Seeing that I was so bored, my mother gave me a task: count the number of small squares on the kitchen sliding door in 5 minutes.

I said, "It's not easy! The villain * * * has six rows, each row has 18 cells, and the column formula is' 6x18 =108 (pieces)'. There are two doors, each with small squares on both sides, and the column formula is'108'. Mom saw that I got it right and gave me a favorable look.

There is mathematics everywhere in life. As long as you have a pair of eyes that are good at discovering, you can discover the mystery.

Math diary, in grades 4 and 7, mathematics gradually became a strange word in people's minds. Today, my father gave me a math problem. Let's have a look!

Title: A rectangular aluminum sheet with a length of one meter and twenty centimeters and a width of ninety centimeters can be cut into a disc with a diameter of thirty centimeters. How many pieces can I cut at most?

I think: should we first convert the unit into 120 cm, then multiply it by 90 cm, and then divide it by 30 cm? Or the conversion unit, divided by 30 cm for multiple, and then multiplied by? When these two methods were at sixes and sevens in my mind, my mother came to the rescue. I told my mother my two methods respectively. My mother thought for a moment and said, "this topic should be done in your second way." First of all, if you do it in one of your ways, it is 120x and so on. 10800 (square centimeter) 10800÷30=360 (square). The answer should be 360. Why are there so many here? If the second method is used, it should be120 ÷ 30 = 490 ÷ 30 = 33x4 =12 (block), which is more reliable. Secondly, you can find it by drawing. " Mom said that when she saw me, I immediately got a heart, ran to get a piece of paper, pen and ruler, and began to draw. It will be finished soon, a rectangle with 12 squares. Every square has a circle and 12 squares. Finally, it proves that my first method is wrong and my second method is right! My mother suddenly asked me, "Will it be now?" I said loudly, "Yes! ..... "After hearing my fluent way of doing the problem, my mother said," But remember, this is not lip service! " "Be sure to abide by it!" I made a police salute, and my mother couldn't help laughing.

After this math problem, I found that my math is not very good. I must work hard! Be a powerful doctor of mathematics! Come on!

Math diary Grade 8 and Grade 4 Whenever I see those papers at home that got full marks, I can't help but think of the story told by my mother-the revelation of decimal point.

That night, after finishing my math homework last night, I finally rested, but I heard my mother shout, "Liu Wei, how did you do wrong again?" I walked over impatiently, looked at the problem and said disapprovingly, "Didn't you just miss a decimal point?"? What's the fuss? " Mom immediately put a straight face: "What? So that's how you see the decimal point. Let me tell a story about the decimal point. "

19xx On August 23rd, the spaceship of the former Soviet Union 1 sent an urgent message, and the parachute could not be opened. The former Soviet government decided to announce the news of the death of the spaceship to the whole country! After hearing the news, people all over the country sighed and felt sorry for Vladimir Komalov, a heroic astronaut. When the Soviet government connected it to the spacecraft's video installation system, Vladimir komarov appeared on TV. He said to his old mother, "mother, I can see clearly, including every hair." What about you? " "Me too!" The old man said with tears in his eyes. "Daughter, how are you? Don't cry, you must be strong and live. You must be careful in your life. The accident is due to the ground inspection, ignoring a decimal point ... "

There are only seven minutes left before the crash. He smiled and said goodbye ... After listening to my mother's story, I understood something. On the next day's math exam, I carefully checked every question and every decimal point. Finally, I got 100. I thought: If I hadn't been inspired by my mother's story, I wouldn't have got 100.

Now, I finally understand the real inspiration of the story my mother told me: you can't be careless about life, even a trivial matter will make you pay a heavy price, even if it has never been made up. The revelation of the decimal point has benefited me for life.

Math diary, Grade 4; math diary, Grade 9; Composition 1 10; Monday is fine.

This morning, my mother and I went shopping in the supermarket. There are many things in the supermarket, such as food, drink, useful and many toys. We first came to the food court and bought a box of my favorite food, Haoliyou brand 15.7 yuan. My mother gave me 100 yuan to settle the bill. 100- 15.7=84.3 yuan.

We came to the vegetable area again, and my mother bought 2.2 yuan, a green pepper. Chestnut 12.4 yuan, bean sprout 4.8 yuan, potato 4.4 yuan, we spent * * money in the vegetable area (2.2+ 12.4+4.8+4.4=23.8 yuan), 84.3 yuan MINUS 23.8 yuan, and now there is 60.5 yuan left. I want to eat milk yellow steamed stuffed bun. We went to the deli and bought a bag of cream buns to go to 5.9 yuan. 60.5 yuan minus 5.9 yuan leaves 54.6 yuan. My mother asked me how much this line costs. Let me see (15.7+23.8+5.9=45.4 yuan). How much is left? Mom gave 100 yuan, and we spent 45.4 yuan (100-45.4=54.6), leaving 54, 6 yuan.

I am so happy to go shopping in the supermarket today!

On the weekend of math diary Composition 2 in Grade Four, my mother sat in front of the computer and surfed Taobao. I asked my mother what to buy. Mother said, "The Spring Festival is coming. I want to buy a pair of shoes for you and your sister. " I asked, "Mom, why don't you go to the store to buy it?" Mom said; "The price of my favorite shoes is 20% off for each pair of 200 yuan, which is 160 yuan. How much are two pairs? "

I quickly calculated: 160*2=320 (yuan)

Mom said, "Not bad. Then you can calculate the online discount for each pair of 120 yuan. How much are two pairs? "

I went on to say: 120*2=240 (yuan)

Mom asked again, "How much cheaper is it to buy online than in the store?"

I said loudly: 320-240=80 (yuan)

Mom said, "Do you calculate fast? Now you know why we don't go to the store to buy it? "

I said, "I see. When can we get new shoes?"

Mom said, "The courier will be delivered to your home at noon tomorrow, so you just wait for the receipt."

Mathematics in math diary 10 grade is closely related to our daily life, especially in commodity trading. Carelessness can lead people astray.

On the occasion of the Spring Festival, my mother and I went to the "Heart of the City" shopping center. Suddenly, my mother saw the limited discount sign in the shop selling cotton-padded clothes. My mother wants to buy a cotton-padded jacket for my father. At that time, my mother took a fancy to one and asked the waiter how much it cost. The waiter said that this dress is new this year, and the original price is 680 yuan. Now she is doing a 25% discount, or attending the 50-day ceremony of 150.

I began to calculate in my mind, 680 times 5 10. If I attend another activity, I can get a 200 yuan gift certificate by paying 680 yuan, and I can buy a pair of pants by adding 180 yuan. The money for buying a pair of trousers is 380 yuan, and I can return the gift certificate of 100 yuan. If I add 99 yuan, I can buy an induction cooker and finally get a gift certificate from 50 yuan. If I add 75 yuan, I can get it. This means that if you spend 25 yuan on two pairs of socks next to you and spend enough 150 yuan, you can get a 50 yuan gift certificate ... Before I knew what this account was about, my mother just paid for the dress. I want to ask my mother what kind of activities she takes part in, but I have no reliable basis.

When I got home, my mother asked my father to try on the cotton-padded clothes. I introduced my father to the activities of the shopping mall, and my father said; "Mom, it's a monkey." I asked my father why. Dad said: "the purchase price of clothes in the mall is about 45% off the sales price." After the 15% discount, he still makes a profit, and he will send a gift certificate when he reaches 150. In order to attract customers to spend more, it is beneficial to customers if they really need something. When you blindly buy things for which gift certificates, which endless gift certificates attract you to fall into the trap of merchants. " Oh; I seem to understand the intention of the merchant. No wonder some people say that "sellers are always better than buyers".

Learning mathematics well and using it properly is really a science. Different positions have different planning and development skills and methods. I want to learn math well and apply it in my life.

Math diary 1 1 In Grade Four, we are studying for promotion and milliliter in school. The teacher asked us, "Guess how many milliliters of water a dripping faucet can drip in one minute?" Some say "20 ml" and some say "30 ml". The teacher said, "Go home and find the answer yourself!" " " .

I am a curious child. As soon as I got home, I took my mother to do the experiment. Start counting 1, 2, ... 60, time is up! I picked up the measuring cup and measured the water. 10 ml of water, only 10 ml of water, so little. My mother seemed to see through my heart and said to me, "think about my four faucets." If each faucet is not closed, how much water can be wasted in one day and how much water can be wasted in one year? " . I calculated it carefully: 10×60×4× 24=57600ml=57. 6L, the water wasted in one day is 57. 6 liters, the water wasted in one year is: 57. 6× 365 = 21024l = 21.024 tons. And we need to waste more than 80 yuan a year per ton of water calculated by 4 yuan. I think: there are 20 faucets in our school: 20×10× 60× 24 = 288000ml = 288L, and 288× 365 =105120L =/kloc. 12 tons, wasting 420 a year. 48 yuan, though not a lot, still lost a lot. If you donate the wasted water to those disaster areas that are short of water, it will not be a small sum. This is my idea. How much water can be wasted if 65.438+0.3 billion people use the tap and leave it on? I began to calculate:

Water wasted in one day:10× 60× 24×130000000 =187200000000 ml =187200000000 l =1872000000 tons.

18720000×4=74880000 yuan; Water wasted in one year: 18720000 ×365=6832800000 tons; 6832800000× 4 = 27331200000 yuan.

The total of 2733 1200000 is about 30 billion! This diversity is enough to bankrupt us. This water is enough to fill the Yangtze River and Yellow River, and this water is enough for many families!

I call on everyone to save water and protect water resources, in order not to let the last drop of fresh water become people's tears!