One day, Sister Xixi played a game for us: two people counted from 1 to 10 in turn, and only counted to 1, 2 or 3 at a time. Whoever reports 10 first wins.

Everyone wants to "knock down" each other, but how can they win 100%? This question has been echoing in my mind, which makes me puzzled.

After returning home, I picked ten stones in a small basket for a novice to operate. I called my father and asked him to play this game with me. I found a pen and a notebook and recorded every step I did. The rule is this: my father and I take turns to take stones, up to three, and at least 1. Whoever gets the last one wins.

I lost the first game. It turned out that my father took it first, and my father made me lose "miserably" in the shortest time; I won the second game first, and I really won. ...

I read the record several times, and finally found that I added up the largest and smallest numbers: 1+3 = 4, and divided the total number of stones by the sum of the largest and smallest numbers, which is 10 ÷ 4 = 2...2. If there is a remainder, I will take it first, and the remainder is only a few stones. If there is no remainder, I will take it first. Now that the remainder is 2, I will take 2 stones, and the sum of the remaining stones and the opponent is a divisor of 3, so I can win.

In order to ensure the accuracy of the answer, I took 28 stones and played with my father again. With the above rules, I am invincible! ! !

It turns out that mathematics is everywhere in life, and they are waiting for you to discover!

Learning mathematics should be used in real life. Mathematics is used by people to solve practical problems. In fact, there will be math problems in life. For example, when you go shopping, you will naturally use addition and subtraction, and you always have to draw pictures when you build a house. There are countless problems like this, and this knowledge comes from life and is finally summed up as mathematical knowledge, which solves more practical problems.

I once saw a report that a professor asked a group of foreign students, "How many times will the minute hand and the hour hand overlap between 12 and 1?" Those students all took off their watches from their wrists and began to set hands; When the professor tells the same question to the students in China, the students will use mathematical formulas to make calculations. The commentary said that it can be seen that China students' mathematical knowledge is transferred from books to their brains, so they can't use it flexibly. They seldom think of learning and mastering mathematics knowledge in real life.

From then on, I began to consciously connect mathematics with daily life. Once, my mother baked a cake, and two cakes could be put in the pot. I thought, isn't this a math problem? It takes two minutes to bake a cake, one minute in front and one minute in the back. At most, two cakes are put in the pot at the same time. How many minutes does it take to bake three cakes at most? I thought about it and came to the conclusion that it takes 3 minutes: first, put the first cake and the second cake into the pot at the same time, 1 minute later, take out the second cake, put the third cake and turn the first cake over; Bake again 1 min, so that the first cake is ready. Take it out. Then put the reverse side of the second cake on it, and turn the third cake upside down at the same time, so it will be all done in 3 minutes.

I told my mother about this idea, and she said, actually, it won't be so coincidental. There must be an error, but the algorithm is correct. It seems that we must apply what we have learned in order to make mathematics serve our lives better.

Mathematics should be studied in life. Some people say that the knowledge in books has little to do with reality now. This shows that their knowledge transfer ability has not been fully exercised. It is precisely because learning cannot be well understood and applied in daily life that many people do not attach importance to mathematics. I hope that students can learn mathematics in their lives and use mathematics in their lives. Mathematics is inseparable from life. If they study thoroughly, they will naturally find that mathematics is actually very useful.

I studied mathematics in the mall from the perspective of the buyer of mathematics.

As a buyer, the most important thing is to shop around. When buying a dress, you might as well write down the brand, size and price first, and then go to other stores for comparison. The price of a commodity is purchase price+freight+tax+manufacturer's profit, as well as a series of additional costs such as store rent and employee salary, so the selling price is often much higher than the value of the commodity. There is actually a better way to save money-online shopping. Online shopping is much cheaper. On the Internet, the price of an item is purchase price+freight. A three or four hundred clothes may only sell for fifty or sixty online, which is very affordable. Even the freight is much cheaper. So, I think we should choose the right things in the mall now, remember the brand, article number and the right size, and then buy them online. Of course, some things can't be bought online, so we should shop around and choose the most affordable one before buying. There may be many people who think that you can get a good product at a lower price, but there is no good product at a lower price ... I can say that as long as you master the method, you can buy good things at a lower price. The same commodity, cheap or expensive, which would you choose?

Everyone knows that things on the Internet are cheap, but they are more risky. This requires us to be vigilant! Merchants who sell things online are reputable, and this reputation is directly displayed on the webpage for buyers' reference. At the same time, there are volume, favorable comments and buyer's messages, which are all set by shopping websites to prevent online scammers from cheating. Now online shopping is very transparent, and you won't lose money if you visit more.

After all, online shopping is still risky, so let's take a look at the activities in the mall. There are many activities in the shopping mall, which are very attractive. Is there any small trap? At this time, we need to use our mathematics!

"Buy one get one free, get 200 for over 200!" Yo, look, here comes the activity!

1. Complete coupon sales campaign

Every holiday, we walk in the busy street, and the promotional signs of "200 for 200" can be seen everywhere. Consumers flock to shopping malls, which are crowded with people, and snapping up is a common occurrence. In fact, the merchants have already laid their wishful thinking in their hearts. As the saying goes, only buy at a loss, don't sell at a loss, and "sending 200 yuan coupons for over 200 yuan" is just a sales promotion method for merchants, which hides mathematical problems.

Just say that 200 yuan sent a shopping voucher to 200 yuan. A customer first bought a cashmere coat from 490 yuan and gave a shopping voucher from 400 yuan. At this time, ordinary customers will have a feeling of picking up the 400 yuan shopping vouchers, so they will have a strong desire to buy and want to spend them quickly (ordinary merchants' shopping vouchers are limited in time, and will expire if they don't spend them for a certain period of time). So the customer spent 248 yuan on a pair of shoes, and the rest/kloc-0 128 yuan in 50 yuan bought a scarf. So how much cheaper is the customer? We can work out 128+248+490=866 (yuan), which we need to spend without discount. 490/866, the discount is about 56%. This gentleman handled it well, because shopping vouchers can only be used in designated places. If you buy it and give it away, you can buy it ... If this cycle goes on, the merchants will make a big profit! Because you have to spend money in this place all the time, even if the merchants set you up, it really seems that mathematics is really important! ! !

"Look at the newspaper! Look at it! There is a prize ~! Huh? ! There are also mall discounts ~! But which economy? " Look at that! Another activity ...

2. Comparison between prize sales and discount sales

Two advertisements were reported in the newspaper. There are prizes for sale in a commercial building: first prize 10000 RMB 1, first prize 1000 RMB 2, second prize 100 RMB 10, third prize 200 5 yuan, and 15% discount for second-class commercial buildings. Let's think about it; Which sales method is more attractive? Which commercial building is of great benefit to consumers?

In the face of problems, we can't be clear at a glance. In practical problems, there is no limit to the turnover of each group of prize-winning sales in Building A and the number of people participating in the lucky draw, so there should be several answers to this question.

Analysis: (1) If the number of participants is less than 213 (112+/kloc-0+200 = 213), people will think that the chances of winning the prize are greater, and the sales model of the shopping mall will attract customers more. (2) If a shopping mall decides to draw a lottery in a unit time, and there are many consumers in a unit time, then the preferential margin it gives customers is correspondingly small. Because the discount offered by a shopping mall is fixed, * *14000 yuan (10000+1000+1000 =14000 yuan). Assuming that the discounts offered by the two commercial buildings are 14000 yuan, we can know that the turnover of the second commercial building is

"Oh ~ ~ ~ so that's it! It depends on the number of people! It also involves the preferential amount, um ... how important mathematics is! "

Learning mathematics is very important, but the ultimate goal is to apply it to real life reasonably. We should learn to use mathematics!