Math diary in life 1 A few days ago, my mother took me to Beijing to play. When I come back, my mother wants to bring Quanjude roast duck back.
Mother asked her aunt, "How much does a roast duck weigh?"
Aunt said, "A roast duck weighs about eight times."
At that time, I was very puzzled: How much does 8 Liang weigh? I kept asking my mother this question on the way back.
My mother told me, "1 kg = 500g, 1 kg = 10 Liang. Use your brain to calculate how many grams 1 two equals? "
"1 two =50 grams." I blurted it out.
Mom added, "A roast duck has eight ounces of oil. How many grams is eight ounces? " I have to calculate: 1 is 50 grams, 8 Liang? 5840, 8 is 400 grams. I finally figured it out. My mother has always praised me for my love of brains.
Now, I know that 1 two equals 50 grams, 3 two equals 150 grams, and 1 kg equals 500 grams ... There is mathematics knowledge everywhere in life, and wonderful numbers are really interesting!
In the first week of math diary II in Life, we learned about cylinders, so what are the applications of cylinders in our lives?
I found that water pipes are the application of cylindrical knowledge in life. The reason why the water pipe is round is because the impact force of the water flow is the same in all aspects of the cylinder. If the impact force points to one place, the water pipe will break easily. Unlike cylinders, cylinders do not break. Another reason is that the area of a circle is large, and water flows out of a cylinder at the fastest speed. In contrast, water flows out of a square or a circle at the fastest speed. But the circumference of a square and a circle should be the same length, and the circle has the largest area and the fastest water flow.
I found that the wheel in life can be regarded as the application of cylindrical knowledge. It is a cylinder, because the distance from the center of the circle to the circle is equal, and because the circle has the least friction when rolling. Making a circle can also make the car run more smoothly.
I also found that the straws we use to drink milk and drinks are all cylindrical applications. The reason why the shape of a cylinder is needed is because the area of a circle is the largest under the condition of equal circumference, so the cylinder is the most material-saving and will drink faster.
In fact, there are many places to use columns in life. As long as you observe them carefully, you will certainly gain something!
On Friday afternoon in math diary, my mother and I went to the market to buy food. Mom said, I'm going to settle accounts today and let me be a small housekeeper.
We came to the place where tomatoes were sold. A kilo of tomatoes is 3 yuan, and we bought two kilos. A kilo of 6 yuan money.
We came to the place where steamed bread was sold. Steamed bread costs 50 cents each, and we bought three. A * * * is 1 50 yuan.
I want to eat mutton kebabs again. My mother took me to the place where mutton kebabs are sold. We bought 10 yuan, and I happily followed my mother home.
On the way, my mother asked me how much I spent today. If I can figure it out correctly, I will be a housekeeper next Friday. I calculated it carefully in my mind and thought about it. I spent 17 yuan 50 points today. Mom said it was right. I am very happy. I'm going to be a housekeeper again next Friday. I am looking forward to it! ! !
Math diary in Life 4 In our life, mathematics is everywhere. For example, the scores and kilograms we have learned are of great help to me.
Once, grandma went to the store to buy five Jin of jiaozi, and planned to give one Jin to her mother. Grandma wrapped up jiaozi and was about to go out. I looked at it with my eyes and thought: one kilogram should be more than that. Grandma should have one tenth in her hand now, but she has to give one fifth. I quickly stopped my grandmother and took jiaozi in my hand and weighed it again. It weighs only half a catty. Then I weighed half a catty and gave it to my mother. Grandma praised me for being too clever. Thanks to this math knowledge, I didn't send it wrong.
Mathematics plays a vital role in our life. Mathematics comes from life and serves life. Learning math well can help us solve many problems in life.
Math diary in Life 5 Hey, choose a movie. This afternoon, my mother and I went shopping in the supermarket.
When we finished buying what we needed, we were about to leave. I saw sausages on the shelf, so I asked my mother to buy some sausages, and my mother agreed. But just a few steps later, I saw a bag. There are 10 pieces with the same brand and the same weight on the shelf, and each piece is 4.30 yuan. Do you want to buy a pack or a slice? I hesitated. Suddenly, my mind turned and I understood. Just compare and see which one is cost-effective. So I started to calculate: if I buy 10 pieces in retail, each piece costs 40 cents, which is equal to 4 yuan, and the whole package costs 4.30 yuan, which is 3 cents more, so I decided to buy it in bulk. I told my mother the process of my calculation, and my mother praised me for my love of brains. Also, I saw a puzzling math problem tonight. The topic is: 37 students want to cross the river. There is an empty boat at the ferry that can only take five people. How many times must they cross the river with this boat at least?
Careless people often ignore the "empty boat", that is, forget to have a gondola, so they can only take four people at a time. In this way, 37 people subtract one rowing classmate, leaving 36 students, 36 divided by 4 equals 9, and the classmate who worked as a boatman on the other side for the last time also landed 4, so it takes at least 9 trips.
On the day of math diary 6 in my life, my parents and I went shopping in the supermarket. We went to the stationery department first and saw a 60-cent pencil. A watercolor pen is about 60 cents; An eraser costs about 60 cents; A ruler 1.4 yuan; A bottle of ink 2.7 yuan; A pencil box around 20 yuan. We can understand that the price of a watercolor pen is similar to that of an eraser, and the price of eight bottles of ink is similar to that of a pencil case. We then went to the food section and converted the prices of some foods into1000g, and reached the following conclusions: Chinese cabbage 1.3 yuan is the cheapest; Rice 2.8 yuan; Noodles 7.3 yuan; Fast food noodles 22.3 yuan; Bread 24 yuan; Meat 36 yuan; Potato chips are more than 80 yuan; Coffee 95 yuan; Finally, chocolate 150 yuan-180 yuan is the most expensive. It can be seen that unprocessed things are usually cheap, and processed things are usually expensive. Although potato chips look cheap, they are actually very expensive. Besides, they are junk food, so we should eat as little as possible.
Mathematics is really a useful science!
Math diary 7 Triangle in Life You are very important in life.
Today's buildings are not only tall but also stable, thanks to the architects. There will be a tripod on the side of the house, and there will be two small triangles on the horizontal part of the flat foundation of the house, so that the house will be more stable and not easy to deform and collapse.
The windows at home are also triangular. Two fulcrums are fixed on the wall or window frame to form a shaft, and one point is equipped with a handle or button on the other side, which makes it open and close freely, safe and beautiful, and brings convenience and relaxation to our life.
Cabinets are also indispensable in our home. The craftsmen made a triangular wedge on the tenon of the cabinet frame to make the cabinet stand as firmly as a rock. In the modern living room, the triangular sides of some cabinets can be shortened or extended freely, and the cabinets can be divided into several layers, which is faster and easier. It seems that triangles contribute a lot.
Triangle not only appears inside and outside the house, windows, cabinets, computers, but also appears in writing, which is found in many places. For example: on the gate, on the table, on the bike, on the box and so on. Not only that, the triangle has played its greatest skill-fixity in every corner of life.
The fixity of triangle has many indelible functions in life, which makes us more convenient, relaxed and safe. ...
Math diary in life has come in August, and there is one thing I like best-sericulture. One day, I saw 1 grandpa selling silkworms of different sizes near the school. After school, I bought six silkworm babies at 30 cents each, and 0 yuan spent 3×6 = 18 points = 65438+8 points. The next day, I found that six silkworm babies ate about 12 pieces of mulberry leaves, and the silkworm babies grew up and ate more and more. 1 Silkworm ate 4 mulberry leaves on 1 day, so 4×6=24 mulberry leaves were put in every day.
After about 15 days, the silkworm baby spins silk and forms cocoons, like peanuts. 10 days later, when the young silkworm emerged from the "peanut", it became a white moth with 1 pair of antennae, 2 pairs of wings and 6 legs. Two days later, 1 pairs of moths laid more than 100, and 3 pairs of moths had 3× 100=300 eggs. I'm so happy!
I will have more than 300 silkworm babies when the spring blossoms next year. I will definitely give it to my teachers and classmates so that everyone can enjoy sericulture with me!
Math diary in life 9, talking about mathematics, is too closely and indispensably connected with our daily life, and runs through our life. Therefore, it is practical to master mathematics, and it is necessary to learn mathematics well.
For example, people who do business need to learn mathematics, and if they don't know mathematics, they won't settle the price; Doing housework needs to know math, how much to cook, how much water to add, how much time to heat in the microwave oven, how much time to wash all kinds of clothes in the washing machine, how much and how long the air conditioner is suitable, and so on. These all need a digital concept. Therefore, learning mathematics well is indispensable in our daily life and work. It can make our life arrangement more scientific and accurate and avoid blindness.
Mathematics is a widely used subject, especially now and in the future, with the rapid development of high technology.
Sometimes, all kinds of high-tech goods enter the daily life of families. If you don't have good mathematical knowledge, you can't operate accurately, which will cause serious accidents. If you don't have a good mathematical foundation and use advanced products, you will stay in the original life forever.
Let's study math hard! Under the guidance of the teacher, practice the basic skills of mathematics in a down-to-earth manner, accept the wonderful mathematical knowledge step by step and explore the infinite mathematical world.
Math diary in life 10 1 15 Wednesday sunny.
There is mathematics everywhere in life, which plays an important role in life. Mathematics is needed everywhere in life because it can solve many problems in life. My sister used it on her birthday. At noon on Sunday, my sister celebrated her tenth birthday and came to the hotel. I saw a lot of people. She invited six classmates, one sister and one brother, plus me and ten people. Ten of us were alone in a private room, and the cake came. My sister doesn't know how to divide it fairly, because she is worried that if there are too many people and too few people, everyone will be angry.
At this time, I proposed: "We divide this cake into ten parts on average, and each person's cake share accounts for one tenth of the total cake, which is only fair."
"Yes, but what if one tenth of each person is not enough to eat?"
"Then use another method. Everyone cuts as much as possible according to their own appetite, so that no one will have any objection."
In this way, we shared the cake. We ate the cake and were very happy. The birthday party soon ended and everyone went home happily.
Birthday parties let me know how important math is. Only by learning math well can I show myself in front of others.
Math diary in Life 1 1 One day, my mother and I went shopping and saw a full stall. They clamored for their parents to give them money to play. Curious, I also walked over. When I saw it, it turned out that the stall owner had made a big box and set up a game to win prizes. There are 1-20 cards in the big box. Children take one out by hand. If the number on this card is even, you can only get some worthless stickers or cards, but if it is odd, you can win the jackpot and get valuable things such as remote control cars, telephone watches and so on. Every time you play, you only need to give the stall owner 2 yuan.
Strange, why does everyone have stickers? I began to think with my super brain. If the odd number "3" is drawn, then 3+3=6 is even, but the even number "6" needs to be drawn, then 6+6= 12 is still even. Oh, yes, odd+odd = even, even+even is even. So no matter what number is drawn, the probability of even number is 100%, and odd number is impossible. Children will only get stickers, not their favorite toys. The stall owner takes advantage of the children, and he is sure to make money.
In fact, these profiteers have used some tricks in their lives. As long as you use your head, think more and analyze more, you will find out the flaws and you will not be easily fooled. I want to tell all the children and parents that there is no free lunch.
Life in math diary 12 Today is the weekend, and white clouds are floating in the sky. My grandma and I are going to buy breakfast. Go to the door of the store, "uncle, how much is a fried dough stick? How much is a bag of soybean milk? " My uncle said kindly, "A fried dough stick costs fifty cents, and a bag of soybean milk costs fifty cents." At this time, grandma gave me a math problem: how much does it cost to buy 5 fried dough sticks and 5 bags of soybean milk? I thought for a moment and answered, "5 yuan." Grandma asked me how I worked it out. I said, "Fifty cents for each bag of soybean milk, fifty cents for five bags of soybean milk" 5525 "in 2 yuan, and fifty cents for five fried dough sticks in 2 yuan, which adds up to 5 yuan." Grandma said, "There is another way. Guess what? " I patted my head and still couldn't figure it out. Grandma reminded me: "Think of a bag of soybean milk and a fried dough stick as one, that is 1 yuan, aren't those five copies all 5 yuan?" My eyes lit up, this method is really simple!
Math diary in life 13 Today, my mother has to go to work, and she asked me to go to the market to buy food and cook by myself at noon.
My mother gave me a piece of 20 yuan to choose my favorite food. I came to the vegetable section first and saw an aunt selling mushrooms. I think: there are vegetables at home, so you can buy some mushrooms and stir-fry them. So, I asked my aunt, "How much is this mushroom a catty?"
Aunt smiled and said, "This mushroom is not expensive. 2.5 yuan is a kilo. How many kilograms do you want? "
"Auntie, I want two Jin, that is, 2.5×2=5 yuan, 20-5= 15 yuan." I immediately took out 20 yuan from my pocket and gave it to my aunt, and told her that I had to pay 15 yuan.
Walking and seeing delicious cauliflower, I couldn't wait to run over and ask, "Boss, how much is cauliflower a catty?"
The boss said, 0.3 yuan, how many Jin do you buy? "
I said, "Buy 4 Jin, that is 0.3×4= 1.2 yuan." I took 5 yuan out of my pocket and told my boss to give me 3.8 yuan back.
Walking on, I saw my favorite tomato again. So I asked my grandmother, "How much is a catty of tomatoes?"
Grandma said, "2.8 yuan is a kilo."
I said, "Can you make it cheaper, 2.5 yuan?"
Grandma said, "OK, no problem. How many kilograms do you want? "
I said, "Three catties, 2.5×3=7.5 yuan."
I took out 10 yuan from my pocket and told my grandma that she wanted to see me, 2.5 yuan.
Today, I have gained a lot. I not only learned to settle accounts, but also learned to bargain.
Math diary in Life 14 Yesterday, my mother and I went to the supermarket.
After picking things, my mother and I will go to the place where we pay the money to calculate the money. I stood bored and watched the assistant aunt collect money. I saw the assistant's aunt tell her mother a *** 187 yuan, and I saw her hand her 10 yuan from 0 yuan, 2 yuan, 5 yuan, 20 yuan and 50 yuan. When I look at the money, I feel very strange: Why isn't 60 yuan RMB 40 yuan from 3 yuan, 4 yuan, 6 yuan, 7 yuan, 8 yuan, 9 yuan or 30 yuan? I asked my mother curiously, and my mother encouraged me to say, "Think hard and calculate well." I calmed down and thought it over. After a while, my brain seemed to suddenly understand and told my mother, "I know, because as long as there is 1 yuan, 2 yuan, 5 yuan, 3 yuan, 4 yuan, 6 yuan, 7 yuan and 8 yuan can be combined at will, and as long as there is10,20, 50 yuan can also be combined into 30,40,60 yuan." Why do you want 2 yuan 5 yuan? " I said, "It is not convenient to use 1 yuan to form a larger number." Now my mother has a satisfied smile, and I am very happy because I have solved a difficult problem in my life.
In fact, there are math problems everywhere in life. As long as you pay more attention to observation and thinking, there will be many unexpected discoveries!
Math diary in Life 15 This afternoon, my mother and I came to Fat Faxiang Supermarket, where there were a sea of people and a wide range of articles. The first thing that caught our eye was the large and small counters. On one of the counters, a picture of rhubarb was propped up with a stick, which said 15% off gold and entered the living area. There are countless discounted goods in it. What washing powder got a 7.5% discount? Snacks are on sale. "ah! Buy four potatoes and get one free! I immediately became curious about these discounted goods, "Ah! What's the discount on potatoes? What's the price of washing powder now? I asked my mother, and my mother smiled and said to me, "You can solve it with what you have learned!" I suddenly realized that I just learned to discount! I've really thought about it. Current price = original price × discount quantity. The original price of washing powder 14 yuan, and the current price should be 14×70%=9.8 yuan. According to the above principle, it is to buy four packs. Potato "money bought five bags, with 4+ 1=5 bags, 4÷5= 20% off, that is, 20% off. I proudly told my mother my idea of solving problems, and my mother praised me as a clever child.