5th Grade Math Diary 2 5

Today, there is an uncle in the family who I have admired since I was a child, known as Zhuge Liang. I picked up the tea tube and was about to make tea for him, when I suddenly had an idea and asked him: Uncle, do you know why most of the tea tubes are cylindrical?

My uncle asked me rhetorically, "Tell me first, why is this?" I don't want my uncle to underestimate me, I really want to use what I've learned to find the right answer.

Time passed minute by minute, and I was sweating profusely, but I just couldn't find the answer. At this time, my uncle patted me on the shoulder and said to me, "You might as well start with a figure with the same circumference, and the area of the circle is relatively large, and think again."

After listening to my uncle's words, it dawned on me: it turned out that using a cylindrical tea tube can not only hold more tea leaves, but also save materials. Knowing this, I proved my idea in connection with real life and combined with the method of drawing.

I told my uncle about this idea, and he gently stroked my head and said, "You are good at finding mathematical problems from real life and using your brain to solve them. I am sure that you will be the future'Zhuge Liang'

Today, I went to school to register and went home, wrapped my book covers, and began to calculate the expenses I spent this semester.

The first is tuition. The tuition fee is 410 yuan, plus 20 yuan for drinking water, a total of 430 yuan. Then there is the Olympiad Mathematics School's fee of 180 yuan, and it is estimated that there will be 20 yuan for the ride, a total of 200 yuan.

There is also money for exercise books: 2 yuan for "Lesson Pass"; "English Practice" 1 yuan; 2 copies of "Examination Paper Lessons"; "Jiangsu Big Test Paper" 3 books 21 yuan. meta).

Study fee: 430 + 200 + yuan).

Living expenses: I will drink about 5 cartons of milk this semester, 5 30 = 150 (yuan). Each meal is about 2 3 yuan, count it as yuan, yuan).

What else? I bit my pencil and muttered to myself, "And your school supplies." "Hey, Mommy is back.

That's right, and school supplies.

School supplies: 8 yuan for a pencil case, 3 yuan for a pencil case (very cheap, clearance goods), 3 yuan for six pencils, 1 yuan for a rubber dollar, 1 yuan for two triangular rulers, 5 yuan for two mechanical pencils, 8 + 3 + yuan).

Total expenditure: RMB).

Wow, I didn't expect that I, who usually don't spend much money, would let my parents spend yuan on my semester. Looks like I'm going to have to save money!

Thursday, October 13, 2005 Weather: Sunny.

Shenzhou-6 orbits the Earth several times a day.

Today, when the director of the Beijing Aerospace Flight Control Center told reporters: "It takes 90 minutes for Shenzhou 6 to orbit the earth every time. When I heard that, I thought:

So how many times can Shenzhou 6 circle the earth in a day? So I quickly used my brain to calculate: there are 24 hours in a day, and 1 hour is 60 minutes, that is:

24 times 60 is 1440 minutes a day. Then divide 1440 minutes by 90, which equals 16 laps. In addition, Shenzhou 6 will explore space for 5 days, that is, it will circle the earth 80 times.

The astronauts are amazing!

A diary refers to a medium used to record content, and a diary also refers to a notebook of daily notes or a record of what you encounter and do every day.

As a literary genre, diary is an applied essay in the nature of a narrative.

The content of the diary comes from our observation of life, therefore, it can narrate, it can write about people, it can be about things, it can write about scenes, and it can also describe activities.

Literally, it's probably about writing down what happens every day. A diary is a record of what you encounter and do every day, and in some cases, you feel about those things. A daily or frequent record of what happened, what was done, or what was observed, especially a daily record of an individual's activities, thoughts, or feelings.

It's the fifth grade, and you still need someone to help you think about the diary! It's true to write it yourself, and what you learn is your own.

Diary 3, Tuesday, August 9.

In the evening, I saw a problem in the Olympiad book: the apple trees in the orchard were three times the size of the pear trees, and Master Wang fertilized 50 apple trees and 20 pear trees every day, and after a few days, all the pear trees were fertilized, but there were still 80 apple trees left unfertilized. Excuse me:

How many apple and pear trees are there in the orchard?

I wasn't intimidated by the question, the puzzle piqued my interest. I think that apple trees are three times the size of pear trees, and if two trees are to be fertilized on the same day, Master Wang should fertilize "20 3" apple trees and 20 pear trees every day. In fact, he only fertilized 50 apple trees every day, 10 of which were missing, and finally a total of 80 of them were missing.

20 pear trees a day, 160 pear trees in 8 days, and according to the first condition, we can know that there are 480 apple trees. This is to solve the problem with a hypothetical idea, so I think the hypothesis method is really a good way to solve the problem. In the math class that day, Mr. Wang said something like this:

The class is wonderful because of mistakes. —short and meaningful.

In the first half of Year 6, we learn to solve problem problems in proportional proportions. Through the study of several example problems in the book, we have come to the conclusion that proportional images are all straight up or down.

Just as we were about to solve the next problem, I asked: why can't it be an up-and-down line but a straight line? The rest of the day was spent answering my questions.

After arguing for a while, Zhang Yuxuan was also a little confused. I found that other students were also a little confused. The teacher asked me to draw a picture on the blackboard, and we understood what she meant

If the data on the number line is not in order, the image will not rise or fall in a straight line. It turns out that I ignored the characteristics of the number line.

Doesn't this prove that sentence? Because of a mistake I made in class, the class had a deeper understanding of the number axis and proportionality. Therefore, it also made me realize that mistakes are not terrible, but the important thing is to raise them and let everyone solve them together. I've learned that when answering questions, don't be held back by the fear of making mistakes – classes are great because of mistakes.

This afternoon, my mom and I went to the supermarket to buy something.

When we were about to leave after we had bought what we needed, I saw ham sausages on the shelves, so I asked my mother to buy some ham sausages, and she agreed. But just after walking a few steps, I saw a pack of them on the shelves, the same brand, the same weight, there were 10 sticks in it, each pack of yuan. Do you buy a pack by pack, or buy one by one?

I hesitated. Suddenly, my mind turned, and there was, as long as I compared, I would buy whichever one was worth it. So I started to calculate:

If you buy 10 sticks for retail sales, each with 4 jiao, it is 40 jiao, which is equal to 4 yuan, and the whole package costs yuan, which is 3 cents more, so I decided to buy in bulk. I told my mom about my calculations, and she complimented me on my love of using my brain.

I'm sorry I'm gone.