2300÷4400÷4, the first one is 100÷4, so 100÷4 = 25200÷4 = 50. At this time, I found that the difference between 50 and 25 is 25, so 300 ÷. Mathematics also has rules.
3. The origin of numbers
This week, Mr. Zhang continued to tell us the number within 100 million, and taught us some new knowledge, such as omitting four zeros at each level and writing 10 thousand words. If the level is greater than 5 thousand or 5 thousand, enter one, and if the level is less than 5 thousand, write zero.
On Thursday, Teacher Zhang said, "Students, collect knowledge about the generation of numbers after going home today." When I got home, I quickly flipped through the books and looked for information in the "Mathematics Garden" of the Children's Knowledge Encyclopedia.
Today, I want to introduce the origin of numbers: in primitive society, human beings had to deal with fruits, fish, sticks and stones in hunting, planting, fishing and gathering activities. Over time, people had more or less consciousness. Primitive people used to count fingers and toes, or pebbles and sticks. When there are many pebbles, a pile of 10 pebbles is represented by a larger pebble. After reading the information, I realized that Arabic numerals were not invented by Arabs, but by Indians. Arabic numerals, expressed in decimal. This decimal system seems simple and common now, but it is actually evolved by human beings through long-term efforts. At that time, there was a lot of mathematical knowledge in life. For example, we use it when shopping or shopping. As long as we practice often, we will learn a lot of math knowledge.
Step 4 shop
Today, I went shopping with my mother.
We first came to Yang Yang Department Store and then went into the supermarket. I bought two sorbets first, 1.5 yuan one, I took a bag of ham sausage and a bag of 7 yuan, and now I bought a watermelon to spend money on going to 7 yuan. Finally, my mother thought there was no rice at home, so she took a bag of rice and spent 53.5 yuan. When I got to the door, I took two more pieces of chewing gum to exchange for 3 yuan. At the door, my mother asked me how much I spent here. I thought about it and said, "(1.5)+2× 7+53.5+3 = 72 (yuan). Mom, I calculated that it is equal to 72 yuan. " My mother touched my head and said I was so smart.
5. Understanding of large numbers
This week, teacher Zhang taught us to know numbers within 100 million. Teacher Zhang taught us that the progress rate between two adjacent units is ten, and each level has one, ten, one hundred and one thousand, and each level has ten thousand, one hundred thousand, one million, ten million and hundreds of millions, and so on. I also learned the counting units, such as 10, 100, 1000,100,000,1000,000,1000,000. , and focuses on the numerical sequence table within 1 100 million and the names of each counting unit.
Through this week's study, I learned to read and write numbers, but I still didn't understand the composition of numbers when I did the questions.
6,
go shopping
This afternoon, my mother and I went to the vegetable market to buy food.
Mother bought a dollar and a quarter of onions first, and then a five-dollar potato. We bought another fish for six yuan a catty in the aquaculture area and bought four catties. My mother asked me how much it was. I answered "twenty-four" in one bite. Mom smiled. When we got home, I helped my mother with her math. Today, I spent 30 yuan 30 cents on groceries! I am so happy this day!
7. Today, I installed three hinge plates at home, and I counted 68 hinges on one plate. At this time, my father asked me, "If there are six people eating, how much will each person get?" I wrote a formula: 3×68÷6. I thought: First of all, how many hinges does 3×68 have? I calculated vertically, and a * * * is 204. It is very easy to know the total number of hinges and then distribute them to six people equally. 204÷6, the result is 34. I told dad to eat 34 hinges each.
8. Revenge
Last night, we went to a Muslim restaurant for dinner. We ordered three courses, namely: a spinach, a beef stew and a half-baked rabbit. We'll settle accounts after dinner. Half a halogen rabbit 15 yuan, spinach 5 yuan, beef stew 8 yuan; Zhanshui and Fange 1 yuan. 15+5+8=28 yuan, 28+ 1+ 1=30 yuan, I will give a * * * to 30 yuan. Mom praised me for being so smart! My heart is sweet after listening to it.
9,