Finally, MINUS the income and expenses that come and go,
You will know how much you have earned and lost this year, and what has been used in it? Math!
Another example is:
During the Spring Festival, many relatives and friends will visit at home. At this time, we must prepare some new year's goods and firecrackers. Now, we have to ask math for help again. Let's compare 5 yuan's "Monkey Climbing Up", "Five-color Tree" 10 yuan, and "Wonderful Pen Makes Flowers" 15.3 yuan. Look at that.
However, once used wrongly, there will be trouble:
During the Spring Festival, many people are willing to have a happy event, such as buying land, building a house and moving, but if the figures are wrong, it will be miserable! For example, if you want to buy a 78-square-meter piece of land, but you accidentally miss the "7", your new home will become a "pigsty", and the area unit can't be wrong. If you add the word "Li" (square centimeter) after "square", you will only have a dog in your house.
Although mathematics is a great contributor to us humans, if we humans can't use it, it is still "not good for the world". Therefore, we must use our brains and use mathematics to make our life more convenient.
Magical mathematics is actually around us. Let's start with every little thing around us, and you will find that this magical mathematics affects us all the time and helps us.
I love you-magic math!
Second, storage
Shen
Every Spring Festival, I always receive lots and lots of red envelopes. Of course, this year's Spring Festival is no exception. I put all the lucky money I got and the pocket money I saved in peacetime into the bank. So far (once a year), I have saved several certificates of deposit.
I never asked about certificates of deposit before. Recently, I got a certificate of deposit with principal, tax and interest written on it, and I was stupid because I don't know anything about these terms!
When I got home, I began to ponder. But after thinking for a long time, I still have no clue, but I am full of doubts. I have no choice but to ask my grandmother and teacher shamelessly. I asked doubtfully, "Grandma, what does the headmaster do?" "The principal is the original amount deposited in the bank, which is called the principal." Grandma said. "Then why is the amount written on the certificate of deposit more than the actual principal after withdrawing money?" I asked again. "That's because the total amount on the deposit certificate after withdrawal is obtained by adding the original principal (interest minus 20% tax). You understand this time! " But I know a thing or two. Grandma finally listed the formula and told me: for example, the annual interest of1000 yuan is X yuan, then the annual interest of 10000 yuan is1000 yuan. The tax is 100 x times 0.2. 100x-(100x-(100x 0.2) can get pure interest. The net interest plus the money actually saved is the total amount due (RMB). I then asked, "Grandma, if I want to withdraw money in advance, how should I calculate the interest?" Grandma said: "In that case, the deposit interest will be calculated according to the current deposit interest, and it is best not to withdraw it in advance as a last resort."
This time, I learned a lot about saving, which broadened my horizons and increased my knowledge, but it also made me feel that mathematics is actually around us. We should learn math well and use it.
Math is good, use it to solve some common problems in life.
Title.
Auntie, you have the wrong change!
Yuan ruoda
Today is February 6th, and the Chinese New Year will be celebrated the day after tomorrow. In the evening, my parents and I went to Hualian Shopping Center to buy new year's goods. Hualien is crowded with people. Sure, in the supermarket.
The superficial goods are dazzling, dazzling! We selected the items as quickly as possible, including my favorite snacks, potato chips, Pepsi-Cola, nutritious breakfast cake, Jinri American ginseng and Great Wall dry red wine.
After paying the money and looking at the long receipt, I was dumbfounded. Mother asked me to compare the receipt with the goods to see if there were any mistakes. I have a look, 4.5× 2+35+17+100× 2+6+15+25. These numbers seem to have life, and they dance around me, dazzling me. After a long calculation, I finally got the result. A * * is 3 16 yuan 70 points. My mother paid 350 yuan, and she should get back 33 yuan's corner 3, but the clerk only found 32 yuan's corner 3. Is this right or not? I recalculated, and the salesperson really missed 1 yuan. After I talked to my mother, she asked the clerk for 1 yuan. I think: the clerk must have given me the wrong change because he is too busy and tired at work.
Through this incident, I found that there are many interesting math problems in my life. As long as you observe carefully, these math problems are around you.
Fourth, the code list
Liu Menglan
After lunch today, Uncle Xiao Zhang asked me to help him remember the clock. Anyway, I have nothing to do, so I agreed. 20.2,21,20.7 Soon, the numbers ran all over the code table. I gave my own code table to Uncle Xiao Zhang, but he asked me to help him calculate it. I thought to myself, forget it. So I said yes.
Each line of the code list has 1 1 spaces. Note every 1 1 spaces, and then add up each note. The first time I took notes, it was 224.2, but it became 244.9 when I checked it, so I changed 224.2 to 244.9. But when I checked again, it became 204.4. Strange, 5 20.7, 1 20. 1, 1 2 1, 2 19.8, 1 20.2, 1 20, 20.7× The result is 244.9-224.2 = 20.7, and I calculated 20.7 more. I see.
Just when I was happy, I found that a corner on the code table had been blurred by me. Mathematics in life is really not simple!
5. Amway Nutrilite products
Zhudatian
Mathematics is everywhere in life, depending on whether you pay attention or not.
You should also use math when shopping. Dad is going to Jiaxing to buy Amway Nutrilite products today. It turns out that the market price of adult protein powder is 295 yuan per can, 236 yuan if there is a preferential customer card, and 325 yuan per can for children protein powder. If there is a preferential customer card, it is also a 20% discount in 260 yuan. During the Spring Festival, in order to repay the market, Amway had a big sale. There is a gift box, which contains two tins of adult protein powder. Each gift box costs 424.8 yuan, which is 23.6 yuan lower than that bought separately. The children's gift box is 364.8 yuan, which is more favorable than buying it separately in 90 yuan. Now dad has 5000 yuan in his pocket. How many adult gift boxes can he buy? How many children's gift boxes? If you want both, what is the most reasonable way to buy a * * 13 gift box? I made a list for my father:
Program Adult (Listening) Children (Listening) One * * * (Yuan) with (Yuan) left.
1 1 12 4862.4 137.6 2 2 1 1
486 1.4 138.6
3 3 10 4822.4 177.6 4
four
9 4982.4 17.6
We can see from the table that the third scheme is the most reasonable.