Reflections on 10 Stories in Mathematics Books

Today, my family went to KFC in Longgang to eat a family set meal.

When we got there, people were always crowded. We finally ordered good food and found a seat to sit down. Here comes the dish. It's a big set meal. There are 12 chicken legs in it. I thought: how can we split it equally? Then I remembered the division of 12÷3=4. We each have four drumsticks. Later, I ate my mother's 1 chicken leg and my aunt's two chicken legs. My aunt said, "You can't eat this for free. Let me ask you, how many points did you eat? " How many more servings do you have to eat before you can finish them all? "I thought about it and replied," I ate 7/ 12, and then I ate 5/ 12. I ate all of them. "Fortunately, I learned the knowledge of fractions and can answer questions correctly.

2. Little Bear's mother is ill. In order to earn money to treat her, Bear gets up before dawn every day to go fishing in the river and sell fish in the market.

One day, when Xiong Gang set up the fish stall, the fox, the black dog and the old wolf came. When Bear saw a customer coming, he hurriedly called, "Buy fish? I just caught this fish. How fresh! " The fox turned the fish over and asked, "How much is a kilogram of such fresh fish?" "The bear is all smiles." Cheap, four yuan a kilo. The old wolf shook his head: "I am old and my teeth are falling out." I just want to buy some fish. The bear looks very reluctant: "I sell the fish to you, so who should I sell the fish head and tail to?" The fox wagged his tail and said, "Yes, no one wants to buy the leftovers, but Uncle Wolf has bad teeth and can only eat some fish. You know what? Black Dog and I are good at each other. One of us buys a fish head and the other a fish tail, which not only helps Uncle Wolf, but also helps Brother Xiong. "The bear clapped his hands, but he hesitated." Good, but at what cost? "The fox rolled his eyes and replied," 2 yuan is 1 kg, fish head and fish tail are 1 yuan is 1 kg. Isn't it 4 yuan 1kg? "The bear drew a picture on the ground with a stick, and then patted his thigh:" OK, let's start! " "The four of them started work together, and in a short time, the head, tail and body of the fish were separated. Once the bear weighed, the body of the fish was 35 kilograms of 70 yuan; Fish head 15 kg, fish tail 10 kg, 10 yuan. The wolf, the fox and the black dog carried the fish on their backs. They quickly ran into the Woods, matched the fish head and the fish tail and divided them equally again. ...

On the way home, Bear thought: According to 4 yuan 1 kg, I should sell 60 kg of fish to 240 yuan, but now I only sell 95 yuan ... Bear can't figure it out.

A snail accidentally fell into a dry well. It cries at the bottom of the well. A toad climbed up and whispered to the snail, "don't cry, little brother!" It's no use crying. The shaft wall is too high. If you fall here, you can only live here. I have lived here for many years. I haven't seen the sun for a long time, let alone want to eat swan meat! " The snail looked at the old and ugly toad and thought, "What a beautiful world outside the well! I can never live in a dark and cold well like it! " The snail said to the toad, "Uncle toad, I can't live here. I have to climb up! "How deep is this well?" "Ha ha ha ..., are you kidding! The depth of this well is10m. How can you climb up with such a heavy shell at a young age? " "I am not afraid of suffering, not afraid of being tired. I can always climb out after a while every day! " The next day, the snail ate and drank enough and began to climb the wall. It kept climbing and finally climbed 5 meters at night. The snail was very happy and thought, "At this rate, I can climb up tomorrow night." Thinking about it, it fell asleep unconsciously. In the morning, the snail was awakened by a purr. At first glance, it turned out that Uncle Tu was still sleeping. It turned out that this snail slipped 4 meters from the borehole wall after falling asleep. The snail sighed, gritted his teeth and began to climb again. At night, it climbed 5 meters, but at night, it slipped 4 meters. Climb and climb, and finally the strong snail climbed onto the well platform. Can you guess how many days it will take snails to climb the drilling platform?

When Gauss was in the second grade of primary school, once the teacher wanted to have a rest after teaching addition, he asked the students to do some calculations. The topic is:1+2+3+4 ..........+96+97+98+99+100 =? I thought the students would be quiet for a while, but I was about to find an excuse to go out, but Gauss stopped me! It turns out that Gauss has worked it out. Little friend, do you know how he did it? Gauss told everyone how he worked it out: add 1 to 100 and 100 to1; Line up in two rows and want to add, that is:1+2+3+4+………………+96+97+98+99+100+99+98+97+96+……+4+3+. 1+10 1+1* * has one hundred101,but the formula is repeated twice, so it is 65438+.

One Sunday morning, my parents and I were watching TV at home, and there was a basketball game on TV. After watching it for a while, my father suddenly said to me, "Qiqi, let me test you a math problem to see if you can?" I opened my mouth and said, "OK, no problem." Dad thought for a moment and said, "suppose the red team throws eight balls a minute and the blue team throws six balls a minute." After they threw together for 8 minutes, the blue team improved its hit rate by 65,438+00 balls per minute, while the red team only threw 6 balls per minute due to lack of physical strength. How many minutes later, the red team and the blue team only threw six balls? I thought for a while, but after a long time he still didn't come up with it. After a long time, I really couldn't think of it, so I had to say shyly, "I can't do without a manuscript." "I know that even if I have a draft, I may not be able to do it.

At this moment, my mother said to me: "It turns out that the red team throws two more shots a minute than the blue team, and one * * * throws eight minutes, which is 8×2= 16 (one); Later, the blue team overtook the red team and threw four more balls per minute. How many minutes does it take to throw 16 balls? 16÷4=4 (minutes), it takes 4 minutes to catch up. " I said, "It's so simple! Why didn't I think of that? " Dad smiled and said, "Is it simple? This shows that there is something wrong with your thinking. In real life, we should be good at discovering things and finding out their laws, then you will feel that mathematics in life is much more interesting than that in class. "

6. In the mysterious kingdom of mathematics, the two "little famous" numbers "0" for the fat man and "1" for the thin man often argue over who is important. Look! Today, two small enemies met in a narrow way, and another war of words was launched between them.

The thin man "1" spoke first: "Hum! Fat' 0', what's so great about you? Just like 100, what's the use of you two being fat without my thin'1'?"

Fat man "0" is not convinced: "Don't be overbearing in front of me. Think about it. Without me, where can you find other figures to make up 100? "

"hey!" "1" is not to be outdone. "If you are arrogant again, you are nothing. Look! 1+0' is not equal to myself. What's your use? "

"Let's go! The result of'1× 0' is not me, and your'1'is also useless! " "0" is tit for tat.

"You ..." "1"paused and improvised. "Anyway, your' 0' doesn't mean anything!"

"This shows that you have little knowledge." "0" said unhurriedly "You see, in daily life, the temperature is 0 degrees. No temperature? For another example, without my starting point on the ruler, how can there be'1'?"

"No matter how you compare, you can only do the middle number or mantissa, such as 1037, 1307, and you can never lead." 1 "said confidently. Hearing this, "0" said more confidently: "This is impossible, such as 0. 1.

Seeing that the fat man "0" and the thin man "1" both blushed, no one would let anyone, and the other people watching were very anxious. At this time, "9" had a brainwave and made a pause gesture: "Don't argue, both of you. Look at you, which number is better than me,'1'and' 0'? " This ... "Fat man" 0 "and thin man" 1 "are speechless. At this time, "9" said calmly: "1" and "0". In fact, as long as you stand together, aren't you older than me? "1" and "0" looked at each other, and it took a long time to scratch their heads and laugh. "That's right! The power of unity is the most important thing! " "No.9 said seriously.

7. In the electronic calculator exhibition center of Mathematics City, the sales staff skillfully operate all kinds of electronic calculators and calculate various problems. People who watch them exclaim from time to time, which shows how fast and accurate the calculation is. Many primary school students in the crowd are holding their parents and clamoring to buy electronic calculators. With it, it would be great to start doing math problems!

"no!" Suddenly, a strange dwarf jumped on the counter, shook his hand and said to the pupils, "children shouldn't use this kind of thing." They should cultivate their own computing ability and learn simple algorithms from an early age. With good algorithms, they are sometimes faster than calculators. "

Everyone focused on the dwarf, and when they looked carefully, it turned out to be a small "5" nicknamed "half".

"What? Can you calculate faster than my calculator? " The clerk asked strangely. Little "5" said, "If you don't believe me, let's try." Then, the little "5" said to everyone, "All you have to do is quote a number and multiply it by 5. Shop assistant, please use the electronic calculator to calculate and see who is faster? "

"good!" Everybody shout together. Someone in the audience reported the formula "246×5" first.

1230 "and" 5 "blurted out.

"3 14×5、289×5……"

"1570, 1445 ..." The little "5" came out in one breath.

Before the salesman could finish the operation, the number was told by the little "5"

"good!" Everyone applauded warmly. Little "5" smiled and said, "This is called" zero plus half "because 5 is half of 10. If a number is multiplied by 5, expand it by 10 times, and then fold it in half. For example, 246× 5 = 2460 ÷ 2 = 6544.

"Let's have another game," said the salesman unconvinced.

"Well, let's use the last digit 5 to calculate the square of any two digits," said Xiao Wu.

"equal to 3025." The little "5" was really fast, and it signed up at once.

At this time, even the shop assistants admire the little "5" for his glib tongue. Xiao "5" said, "Any last digit is the square of two digits of 5. Just multiply its ten digits by a number larger than it by 1, and then add 25 to the product. For example, 752 = 5625, and 56 is the product of 7 and 8.

"Ha ha, that's fast."

"Half, really smart, dare to compare skills with calculators; The method is wonderful, fast and accurate, and it is the big star of the mathematics city. " I don't know who made up some jingles and made everyone laugh.

8. Bajie opened a grocery store. One day, the little monkey came to make a catty of vinegar for his family. The little monkey came to Uncle Shi's shop and shouted, "Uncle Shi, make vinegar!" " "

Bajie asked the little monkey how much vinegar he used. The little monkey said, "Not much, just one or two."

Pig was surprised and asked, "What's the use of vinegar?" The little macaque said, "Of course!" Pig asked again, "Is one or two enough?" The little monkey said, "Not enough, let's play one or two more!" " "

Pig asked again, "Two taels is not much?" The little monkey said, "Let's play once or twice." Bajie hit again once or twice. The little monkey said, "Let's play once or twice ..." In this way, the little monkey played twelve ounces of vinegar, which is a catty of vinegar.

After playing vinegar, Pig said, "A catty of vinegar is 84 cents." The little macaque unhurriedly took out 80 cents and gave it to Uncle Bajie. Bajie took the money and said, "Don't cheat, there is still 4 cents left!" " The little macaque asked, "Uncle Shi, how much is a cup of vinegar?"

"Of course," Pig said, "one or two vinegar is 80 cents, 4 cents is discarded and 8 cents is collected." The little monkey said, "So, one vinegar or two is 8 cents." "Of course," Pig said. The little monkey added, "Twelve vinegar and eighty cents!"

"That's right," Pig said. The little monkey said, "I gave you 80 cents." How can you say that you still need 4 cents? " Bajie was speechless, lost another 40 cents, and watched the little macaque go away with vinegar.

8. Bajie opened a grocery store. One day, the little monkey came to make a catty of vinegar for his family. The little monkey came to Uncle Shi's shop and shouted, "Uncle Shi, make vinegar!" " "

Bajie asked the little monkey how much vinegar he used. The little monkey said, "Not much, just one or two."

Pig was surprised and asked, "What's the use of vinegar?" The little macaque said, "Of course!" Pig asked again, "Is one or two enough?" The little monkey said, "Not enough, let's play one or two more!" " "

Pig asked again, "Two taels is not much?" The little monkey said, "Let's play once or twice." Bajie hit again once or twice. The little monkey said, "Let's play once or twice ..." In this way, the little monkey played twelve ounces of vinegar, which is a catty of vinegar.

After playing vinegar, Pig said, "A catty of vinegar is 84 cents." The little macaque unhurriedly took out 80 cents and gave it to Uncle Bajie. Bajie took the money and said, "Don't cheat, there is still 4 cents left!" " The little macaque asked, "Uncle Shi, how much is a cup of vinegar?"

"Of course," Pig said, "one or two vinegar is 80 cents, 4 cents is discarded and 8 cents is collected." The little monkey said, "So, one vinegar or two is 8 cents." "Of course," Pig said. The little monkey added, "Twelve vinegar and eighty cents!"

"That's right," Pig said. The little monkey said, "I gave you 80 cents." How can you say that you still need 4 cents? " Bajie was speechless, lost another 40 cents, and watched the little macaque go away with vinegar.

Once upon a time, there was an old man. On his deathbed, his three sons gathered at the bedside.

He said to his sons, "I have prepared 17 horses for you and distributed them to three people." When the horse is divided, the boss contributes the most and divides it into half. " The second child, one third; The third is the youngest, so you can take one ninth of the total. "

After barely saying these words, the old man died. When the three brothers executed their wills, they agreed that these horses were their father's favorite things before his death, and they must never divide any of them into several pieces. But what should they do if the will is fully observed?

Just as their old uncle rode here, he raised his eyebrows and said, "I'll share."

Guess, how did the old uncle divide the horse?

Because I want everyone to get an integer horse, according to the will, when dividing horses, the number of horses should be a common multiple of three denominators. The least common multiple of denominators 2, 3 and 9 is 18, so the total number of horses when splitting horses should be a multiple of 18. The old man left his sons 17 horses, and the old uncle brought one himself.

Ready, the old uncle began to read and execute the will:

"... when dividing horses, the boss contributed the most, accounting for half ..." After reading this, the old uncle counted nine horses and asked the boss to take them:

Second, one-third of the total ... "After reading this, the old uncle counted six horses and let the second one lead him:

"The third child is the youngest. You, take one ninth of the total." After reading the last sentence, the old uncle counted two horses and let the old one take the lead:

The sum of the horses divided by the three younger generations happened to be left by the father 17 horses;

9+6+2= 17.

There are 18 horses in the racecourse, and now there is only one left. Of course, my uncle borrowed it temporarily, and now it is still returned to its owner.

10. During the Warring States Period, Qi Weiwang and General Tian Ji raced horses, and Qi Weiwang and Tian Ji each had three good horses: mounted, mounted and dismounted. The race was held in three times, and each horse bet 1000 dollars. Because the horsepower of the two horses is almost the same, and Qi Weiwang's horse is better than Tian Ji's, it is generally believed that Tian Ji will lose. However, Tian Ji adopted Sun Bin, Ma Zhong was dismounted by Ma Zhong of China, and Qi Weiwang was dismounted by Ma Zhong of China. As a result, Tian Ji defeated Qi Weiwang 2-/kloc-0-,which is an example of China's ancient substitution game theory to solve the problem.

Here is a game played by two people: take turns to report numbers, and the number reported cannot exceed 8 (nor can it be 0). Add up the figures reported by two people, and whoever reports more figures will win if the total is 88. If you are asked to sign up first, how many times do you have to sign up for the first time to win?

Analysis: Because everyone reports at least 1 and at most 8 at a time, after someone reports, another person will find a number, so the sum of this number and a reported number is 9. According to the rules, whoever quotes the sum of 88 will win, so it can be inferred that whoever quotes the sum of 79 (= 88-9) will win. Whoever reports 7 first wins. Therefore, the winning strategy of the first whistleblower is: report 7 first, and then if the other party reports K( 1≤K≤8), you report (9-K). In this way, when you quote the number 10, you win.