How does a third-grade student write about math diary?
In this afternoon's math contest, there was a question on the test paper: It is expected that 40 machine tools will be made every day in the factory, and the expected number of days will just be finished. Actually, 48 machines will be made every day, and they will be finished four days in advance. How many machine tools will be manufactured?
When I saw the problem, I thought to myself: this problem is not only the number of days multiplied by the number of sets made every day, but also the number of days, so go find it. It says that it will be completed four days ahead of schedule, so that we can know how many units have been completed ahead of schedule. 40 times 4 equals 160 units; We use 48 MINUS 40 to equal 8 sets, and we can find that 8 more machine tools are made every day; 160 divided by 8 gives the number of days-20 days.
Great! Then I multiply 20 by 48 to figure out how many machine tools to make, which is 960. Hee hee, ecstatic! To ensure a good result, I will check it again. 960 divided by 40 equals 24 days, and 24 minus 20 equals 4. I really did it right! I'm great! My heart praised myself, while secretly complacent, a bit high. ...
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 in order to facilitate its application in life.
How to write math diary, the third grade of the second primary school?
I was stumped by an application problem when I was doing the problem today. The title of this question is: Xiaohua is 3 years old and Dad is 26 years old. In a few years, his father is three times as old as Xiaohua. I'm confused.
Then my mother came back and I asked her. Mom helped me analyze it: according to the conditions of this topic, the "age difference" between dad and Xiaohua this year is 26-4 = 24 (years old). Then draw a picture according to the relationship that "Dad is three times older than Xiaohua". The two of us began to draw.
After drawing the picture, I immediately understood that after several years, the "age difference" between them was still 24 years old. Then, according to the solution of the differential problem, we can find out Xiaohua's age in a few years, and subtract 2 years from Xiaohua's age in a few years to know how many years have passed.
The solution is: 26-2 = 24 years old.
24(3- 1)= 12 (years old)
12-2 = 10 (year)
A: 10 years later, my father is three times as old as Xiaohua.
Mom asked me to check again. 10 years later, is dad three times as old as Xiaohua?
(26+ 10)÷(2+ 10)=36÷ 12=3
Yeah! I got it right. It seems that you have to draw a picture first to do the problem, and you can see it at a glance when you draw it.