22 5th grade 300 word diaries

Chapter 1: Buy oranges

Mathematics is everywhere in life. For example: Grocery shopping! Buy stationery! Measuring cloth and so on, all need to use mathematics.

This semester, the teacher taught a new knowledge, which is the multiplication and division of decimals. This knowledge has helped me a lot!

Last night, my mom went shopping for oranges together. The oranges are a pound of yuan, and my mother bought a pound and should have paid for it. But the salesman was careless and didn't know how to calculate it, so it was calculated as 9 yuan.

Fortunately, I used the knowledge of this semester's Protestant, and after doing a few calculations in my head, I immediately corrected the salesperson's mistake.

Not only did the salesman praise me for being smart, and I knew how to multiply and divide decimal numbers so little, but I was also going home'On the way, my mother also praised me, saving her yuan, and the knowledge she learned can be used in life.

Oh, yes! If you don't learn this math well, you will lose not only this yuan in the future, but maybe hundreds, thousands, or even hundreds of millions!

Chapter 2: Grade 5 Mathematics Diary

I was having fun with my sister, and my grandmother called me in and asked me to settle an account for her.

Grandma bought 3 catties and 4 taels of eggs, the price per catty is 3 yuan and 5 jiao, grandma paid 12 yuan, how much should I get back? As soon as Grandma's words fell, Grandpa said:"Find 1 dime!

I didn't believe that my grandfather could calculate so quickly, so I used the math I had learned to calculate: unit price multiplied by quantity = total price; The money paid and the money spent = the money recovered, which is exactly the same as the grandfather's score, looking for 1 dime. I asked Grandpa why he counted so quickly.

It turned out that the grandfather divided 3 yuan and 5 jiao into 3 yuan + 5 jiao, first multiplied by 3 = yuan, and then multiplied by half of the two is 17 yuan, so a total of yuan was spent, 12 yuan was paid, of course, a dime. After my grandfather finished speaking, I understood that he used the multiplicative distributive law.

Through this incident, I realized that mathematics can be used everywhere around us. Let math do the work for us!

Chapter 3: Grade 5 Mathematics Diary

Today, I took 10 yuan to the 3rd floor of Haoyouduo supermarket to buy books.

I searched and found a copy of "Myths and Legends", and as soon as I looked at the cover, I knew that there were many wonderful stories in it. I decided to buy it, but when I saw the price, I was stunned, and it turned out that the book was 11 yuan. I was reading this book and feeling for the money in my pocket, which really embarrassed me!

The saleswoman saw my embarrassed look and asked kindly, "What's the matter, little friend?" I said shyly

I want to buy this book, but I don't have enough money. She asked, "How much money did you bring?"

Only $10. I said. Auntie smiled and said:

Children, you see that the pricing board also reads, 'Discount books, all 10% off'. I asked, "What do you mean by 'all 90 folds'?"

The aunt said: "It is to collect money according to nine-tenths of the list price, for example, a book of 10 yuan is only charged 9 yuan." ”

I did the math, and this book only costs 9 yuan and 9 jiao. "That's right! I thanked my aunt repeatedly.

Today, I am so happy that I have not only bought a satisfactory book, but also learned knowledge!

Whenever I open the pencil case and see the black pen, I can't help but think of an incident that happened a few days ago.

It was Thursday night in the nursery class, and I was writing my homework, when Mr. Zhu walked in and gave me a proposal for the Young People's Congress, asking me to fill it out before class and give it to Mr. Wang, and asked me to fill it out with a black pen. When I heard it clearly, I picked up a black pen and began to write. As I wrote, the handwriting on the paper faded, and when I looked, there was no ink in the pen.

What can I do? I'm about to pay it, ask my classmates to borrow it? Everyone has to do their homework, and it's impossible to lend it to me.

I'm as anxious as an ant on a hot pan, and I don't know what to do. Suddenly, Xiao Yi, who was writing her homework, saw it, and asked with concern, "What's wrong, Xiaoting, do you need my help?"

Hurry up! "I can't write it with a pen, but the proposal is about to be handed in, and I'm in a hurry!" "I thought there was all the fuss!

Xiaoyi said, "I'll borrow you." Xiao Qi, who was sitting in front, heard it, turned around and said, "The teacher doesn't require that this homework can only be written with a black pen, and you only have one, which you lend to Xiao Ting, what should you do?"

Aren't you afraid that you will be left behind because you can't finish your homework? Didn't we say okay, let's go to Xiao Gui's house after school today? Xiao Yi smiled and said

Since she has an urgent use, of course I will lend it to Xiaoting first, is the overall situation important! With that, he handed me the pen, and I looked at her with gratitude and began to write quickly. After a while, the proposal was written, and I returned the pen to Xiaoyi, who successfully completed her homework before the class bell rang.

Although this incident is small, it has left a deep impression on me, and a pen embodies the sincere friendship between me and Xiaoyi.