Math diary, Grade Two in Primary School (Ten Articles)
The teacher taught me about centimeters and meters these days. When I learned that, I came home and saw my mother washing clothes. I saw the washing machine. I had a brainwave, took out an uncut pencil from the pencil case and measured it. The washing machine is about five pencils high, about one meter wide and three pencils wide, about 60 centimeters. Finally, I took out my cloth ruler and measured it again. It's only a few centimeters less than my estimate. I'm so happy. -Click to view the whole content.
Whenever a math contest is held in Tomb-Sweeping Day, there will be a sea of people on the mountain, so some swindlers come up with some tricks to cheat people, such as betting on something on a plate.
Prop is very simple, draw a big circle on a board, and fix a rotatable pointer in the center of the big circle with a nail. The great circle is divided into 24 equal squares, and the needles in the squares can rotate. The box says 1-24 equal numbers, which are worthless in the odd box, but almost all even numbers are valuable. -Click to view the whole content.
Grandma bought medicine yesterday, grandma and I went to the drugstore and bought two boxes of pills-Shu Ning, 52 yuan and 26 yuan. Grandma gave her 100 yuan, and the shop assistant gave it to grandma 48 yuan. After I found the change, I calculated it with decimal addition and subtraction. -Click to view the whole content.
Conquer a difficult problem today, I met another math problem, and it took a lot of effort to solve it. The topic is: there are 30 birds in two trees, and 4 birds fly away from the second tree first. At this time, tree A flew to tree B with three birds, and the birds on the two trees were just equal. How many birds are there in each tree? -Click to view the whole content.
Apple Trees In the evening, I saw a problem in the Olympiad Book: the number of apple trees in the orchard is three times that of pear trees. Master Lao Wang fertilizes 50 apple trees and 20 pear trees every day. A few days later, all the pear trees were fertilized, but the remaining 80 apple trees were not fertilized. Excuse me: How many apple trees and pear trees are there in the orchard? -Click to view the whole content.
The observation object "observation object" is really interesting. I didn't expect to find so much mathematical knowledge in the process of observation. Observing an object, one can't observe everything, so one should cooperate with one's study partners. When observing, we should pay attention to identify the main characteristics of the object, think about the difference between observing the same object in different positions while observing, and then communicate with our classmates. -Click to view the whole content.
I want to be a doctor. Today, the teacher wants us to be "doctors". Hey, what does the teacher want us to be doctors for? Oh, it turns out that the teacher wrote a wrong question on the blackboard the other day. -Click to view the whole content.
Interesting Questions During the break, Xiaowen, the "little doctor" in our class, said to the students, "Today, I will give you an interesting math problem. The topic is: two mothers and two daughters are walking by the river. How many people are there at least? " Xiaojun said: "This is not simple! Of course, there are two mothers and two daughters, so there should be 2+2=4 (people). " -Click to view the whole content.
The size of the possibility This morning, I finished my homework and prepared to play a ball game with my father.
I first prepared a big box, and put three red balls, four blue balls and five white balls in the box. The rules of the game are: everyone can only touch it once, and whoever can touch the red ball will be rewarded. -Click to view the whole content.
Math homework One day, I was doing math homework in the classroom. Then, I met a math problem that I couldn't understand. This math problem is: Find the volume of a cuboid. This question gives me two conditions. The cross-sectional area is 30 square centimeters and the width is 6 centimeters. I think: isn't the volume of a cuboid multiplied by its width and height? Why did the topic only give us the area and width of the bottom? I haven't thought about it for a long time and I don't know how to do it. So I went to ask the math teacher.