1. math diary's model essay in the third grade of primary school.
Last night, it was very hot. Dad stopped me when I took out a watermelon to cut. He gave me a question, the title is: cut this watermelon into nine parts and cut out ten skins. See how you cut it? At this point, I thought, well, it's simple. So, I went to get a fruit knife, put the watermelon on the table and cut it. I cut a "meter" shape. If you count, nine dollars is enough, but only nine dollars! Not convinced, I brought another watermelon. When I was about to cut it, my father stopped me. He pointed at me and said, "Oh, how many watermelons did you waste?" Let me cut it! "Dad picked up a fruit knife and told me to watch. I watched the audience carefully. At this moment, a question mark flashed through my mind. What should I do? After dad cut it, I counted it. There were only nine skins, but he cut it in the shape of a well. I looked at my father and said, "Dad, didn't you cut nine pieces?" Dad saw my puzzled look and told me the "hiding place" of the tenth piece of leather. It turned out that the tenth piece of skin was hidden under the mouth in the middle of the word "hmm" before I suddenly realized. At this time, my father looked at me and guided me according to the situation: "There are many things in life. As long as you observe carefully, you will definitely gain something, just like cutting watermelon this time. " I nodded my head.
2. math diary's model essay in the third grade of primary school
I found a very interesting question today. After careful analysis and calculation, I finally "beat" the problem. The topic is this: there are three people in a family. The mother is the same age as the father, and the mother is three times older than the son. Four years ago, the sum of their ages was seventy-two. How old are they now?
As soon as I saw this question, I was blindsided and completely stumped by it. But I know how many people will be disappointed if I "admit defeat" like this!
So, I calmed down and began to analyze slowly, and finally found that this is a double problem. It turns out that the breakthrough of this problem lies in the condition that the sum of the ages of the three people was 72 years old four years ago. From here, we can calculate the sum of the ages of the three people this year: 72+4×3=84 (years old). After finding the sum of the ages of three people this year, we can find out the age of our son this year by solving the problem of sum times: 84÷(3×2+ 1)= 12 (years old). Next, we can calculate the age of parents this year according to two conditions: 12×3=36 (years old).
From today's question, I understand that when encountering difficulties, don't flinch because of fear. The greater the difficulty, the more we must go forward and overcome it.
3. math diary's model essay in the third grade of primary school
Today, my parents and I went to Qilu in Mo Lifeng to buy stationery. There are many things in it, so I chose some beautiful ballpoint pens and highlighters. Take a closer look, the red label on the ballpoint pen has a downward arrow. I asked my mother, "What does this mean?" Mom replied: "This arrow proves that this product is on sale, so it is cheaper to buy it at this time." I said happily, "Mom, that's great. Let's buy more! " "My mother agreed, but said to me," I can only give you money, and you can go to the bank clerk's aunt to settle the bill yourself. "I hesitated and went away. I took three ballpoint pens and a highlighter, and then I looked at their unit prices, a ballpoint pen 2 yuan and a highlighter 3 yuan. Little brain quickly turned up, it should be 2x3+3 = 9 yuan, and my mother gave me 10 yuan. When checking out, the cashier aunt asked me, "How much do you want, little friend? "I can't figure it out, but I don't give change." I immediately replied that I would call 1 yuan. Aunt smiled and gave me a dollar coin. Finally, I went shopping with my parents and went home happily. It was really a pleasant shopping, because it was the first time I paid for it myself.
4. math diary's model essay in the third grade of primary school
During the National Day holiday, my mother took us to travel.1October 2 10, we went to Xiangshawan in Ordos. There are seven adults in our family: Uncle Du, Uncle Zhao, Aunt Zhao, Dad, Mom, Grandpa and Grandma, and there are two children: I and my brother Yihao, there are nine people in our family (7+2 = 9), and 430 yuan is one. This is an adult ticket. Children under 1.2 meters don't need tickets, and those above 1.4 meters are adult tickets. My aunt said that my ticket is 60 yuan cheaper, and my ticket is 370 yuan (430-60 = 370). My mother and grandmother can get a little cheaper at 40 yuan, and their tickets are 390 yuan (430-40 = 390). My brother is 1.6 meters tall, so my brother is also an adult ticket. We spent 3730 yuan (2580+370+390+390 = 3730) on a ticket.
We have no water to drink in the desert. My father and I went to buy water, and bought a bottle of black tea 6 yuan, a bottle of green tea 5 yuan, a bottle of cola 6 yuan and three bottles of water 15 yuan. Each bottle of water 5 yuan (5+5+5 = 15) cost 32 yuan (15+6+5+). We didn't spend any money to go anywhere else. I don't know how much my mother spent on the gas card.
I had a very happy holiday and will help my mother settle accounts in the future.
5. math diary's model essay in the third grade of primary school
I learned a new knowledge today, which is a simple addition and subtraction algorithm. Learned a simple addition and subtraction algorithm, mine. The 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: don't think about the minuend when you do subtraction, or you will 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!