Chapter 1: Mathematics in life can be said to be everywhere in our life. When we pay for things in the supermarket, when we measure the area of things, when we make objects with various shapes such as parallelogram, right angle and triangle … these are the direct applications of mathematical knowledge in our lives. A few days ago, something happened in our family to solve life problems with mathematical knowledge.
When I came home from school that day, I sat in a small chair and heard a "crunch", which scared me to jump. Ha, it turns out that one leg of the chair is loose. "How about we fix the chair?" I said to my parents on impulse. Mom and dad said "yes" with great support. So the whole family began to get busy, looking for tools, holding chairs and nailing. After the "scratching" sound, several big nails were nailed into the loose chair legs. "Hey, it's finally nailed." I clapped my hands and sat up with satisfaction. Crunch. Hey, what's up? What should I do?
Suddenly, I remembered what the math teacher said: triangles can stabilize objects. Yeah, why didn't I think of that just now? I immediately found a small piece of wood, cut it into four small triangular pieces of wood with the same size according to the angle formed by the four legs of the small chair and the chair surface, and then filled the triangular pieces of wood in the gaps between the chair legs and the chair surface respectively, and nailed them firmly. Needless to say, this chair is safe to sit on.
Hey, these numbers are amazing. It seems that I must study mathematics harder in the future, apply mathematics to every bit of life, analyze and solve practical problems in life, and better adapt to the development and needs of society. Make life more meaningful.
Chapter 2: Interesting Mathematics in Life In fact, mathematics is closely related to our life. Today I will tell you a little story about mathematics in life. The content of the story is: Aunt Li went to the supermarket to buy a sweater. The clerk was her neighbor and told her about a sweater, 62 yuan. Aunt Li bought one to go home. The next day, she came to the supermarket again, and the salesgirl introduced her: A new sweater made in 78 yuan is of good quality, and suggested that she buy it. Aunt Li decided to buy three pieces. After checking the account, the salesman said, "You should have given me 234 yuan, but you bought a sweater made in 62 yuan yesterday. If you want to change it, give me 52 yuan money first, and then give me 62 yuan 120 yuan sweater tomorrow. " Aunt Li went home and compared four sweaters, and decided to buy two sweaters from 62 yuan and 1 sweaters from 78 yuan. The next day, the salesman accepted Aunt Li 88 yuan. Aunt Li was really confused during the whole process. Is the salesperson's statement correct?
We can think of it this way first: How many times did Aunt Li pay * * *: 62+52+88 = 202 yuan.
The price of three sweaters is 62+62+78 = 202 yuan. Therefore, it can be concluded that Aunt Li has neither taken advantage nor suffered.
I want to say, "This is the mathematics in our life. To use our mathematical knowledge to solve practical problems in this life, we must keep in mind a principle, that is, no matter how you change, as long as you remember how much money you gave three times, you will not make mistakes. "
In fact, there are many such examples in our life. For example, we often encounter that we need to pay 93 yuan for a pack of things in the supermarket, but you just don't have change, so we gave it to the shop assistant 100 yuan. At this time, the salesman often asks you, "Do you have change for three dollars?" And you happen to have three yuan change, you can give it directly to the salesman, and he will give it to you 10 yuan. Some students will be confused when they encounter such problems. Confused. In fact, as long as we remember: as long as we * * give the salesperson 100+3 = 103 yuan, and the value of our goods is 93 yuan, we will use 103-93 = 10 yuan.
As long as students pay attention, they will find many interesting math problems in life. Mathematics is really everywhere. As long as we pay attention to observation, we will gain a lot of mathematical mysteries.
Chapter 3: Language in mathematical life has taught us to write, but mathematics also plays a very important role in it. Mathematics in life is like a shy little girl who loves to hide and seek. It will be hard to find if you don't look carefully, but there is mathematics everywhere in life. Please look at my math life!
After school on Friday afternoon, my mother said that she would take my brother and me to the department store after dinner. My brother and I were so happy that we kept urging our mother to "cook quickly, we are all waiting for you!" " I want more pancakes. We can only put two pancakes in the pot at a time, and frying one takes 2 minutes. It is also stipulated that the front and back sides need 1 minute. How many minutes does it take the three of us to fry three cakes? "I thought for a long time before I answered," First, put two cakes in a pot and fry them together. A minute later, both were cooked on one side. At this time, you can take out one, turn the other over, put the third one in, fry for another minute, take out the fried ones on both sides, turn the third one over, put the first one in, fry for another minute, and everything will be fine. So it takes at least 3 minutes to fry 3 pieces. "Mom praised me happily:" It seems that you are doing well in math! "At this time, the cake has been fried, but I am still thinking: Yes, mathematics is like this! We finished our meal quickly and set foot on the way to the department store. ...
When I arrived at the department store, I clamored for my mother to buy me something nice. My mother said slowly, "The weight of one bag of chocolate is equal to the weight of two bags of biscuits, the weight of four bags of beef jerky is equal to the weight of one bag of chocolate, and one bag of biscuits is equal to the weight of several bags of beef jerky? If you get it right, I will buy it for you. " Well, it's not easy. According to the weight of one bag of chocolate = the weight of two bags of biscuits and the weight of four bags of beef jerky = the weight of one bag of chocolate, it can be calculated that the weight of two bags of biscuits = the weight of four bags of beef jerky. So, the weight of a bag of biscuits = the weight of two bags of beef jerky. "I replied without thinking. I can't help thanking math from the bottom of my heart. It got me a lot of things.
There is mathematics everywhere in our life, which can bring infinite happiness to careful children, but careless children can't find it!
Chapter 4: Mathematics in Life I am a pupil who likes to study mathematical reasoning. I think those logical reasoning are very interesting and can bring me spiritual satisfaction. One day, when I came across such a problem, I began to meditate. The question is this:
There are three rooms, A, B and C, and each room has a mailbox. The label on the mailbox in room A says: Xiao Wang is in this room. The label on the mailbox in room B says: Xiao Wang is not in this room. The label on the mailbox in room C says: Xiao Wang is not in room A ... Tip: Only one of the three mailbox labels is correct. Q: Which room is Xiao Wang in?
Maybe my mind was a little confused at that time, or I was confused when I saw these three full lines, and my mind was blank. I carefully looked for the conditions between the lines and decided to make a hypothesis through trial and error.
Suppose 1: If the label on the mailbox in Room A is correct and Xiao Wang is in Room A, then the label on the mailbox in Room B is also correct, which does not meet the condition of "only one label is correct" in the title. Suppose one doesn't hold.
Looking up, my father showed a gratified smile and was affirmed. I have more confidence in the next problem-solving ideas.
Hypothesis 2: If the label on the mailbox in room B is correct and Xiao Wang is not in room B, then it is also possible that the mailbox in room A says Xiao Wang is in room A and the mailbox in room C says Xiao Wang is not in room A. But if the label on the mailbox in room C is wrong and the label on the mailbox in room A is also wrong, it means that Xiao Wang should be in room A but not in room A. The two are contradictory, so hypothesis 2 is not valid.
Hypothesis 3: If the mailbox label in room C says that Xiao Wang is not in room A, then the mailbox label in room A says that Xiao Wang is in this room is wrong and meets the requirements. The mailbox on the label of room B is wrong, not impossible, that is to say, Xiao Wang is in room B. It can be seen that if hypothesis 3 is established, the result is that Xiao Wang is in room B.
After I worked it out, I jumped three feet high and happily showed my father the calculated topic. My father praised my active thinking and made me more interested in mathematics. From now on, I will study these interesting math problems harder and explore the mysteries of the math kingdom.