Interesting story of mathematics 1 When Hua was in middle school, in a math class, the teacher gave the students a famous question: "There is a number, three, and two; 5 digits, 5 numbers, and the remaining 3; There are seven places in seven, and there are two left. What's the date? " While everyone was thinking, Hua stood up and said, "23". His answer surprised the teacher and won his praise.
Mathematical anecdote 2 Shiloh, king of Syracuse, asked a goldsmith to make a crown out of pure gold. Because it is suspected that there is silver mixed in it, Archimedes is invited to identify it. When he entered the bathtub to take a bath, the water overflowed outside the bathtub, so he realized that although the weight of objects made of different materials was the same, the discharged water would be different because of their different volumes. According to this truth, it can be judged whether the crown is adulterated.
A group of monkeys were playing by the well, and a gust of wind blew a monkey's hat into the well. He called 18' s friends and fished for his hats one by one from the pine trees by the well. Four monkeys don't climb trees, so they go for hats. Q: How many monkeys got their hats from the well under the tree?
Mathematical anecdote 4 In 46 BC, Julius Caesar, commander-in-chief of Rome, appointed the calendar. Because he was born in July, in order to show his greatness, he decided to change July to "Julian month", and all single months were stipulated as 3 1 day, and bimonthly was 30 days. In this way, there is one more day in a year. February was the month when prisoners were executed in ancient Rome. In order to reduce the number of people executed, 1 day was reduced in February to 29 days.
Interesting story of mathematics 5 The manufacturer who sells pianos has 20 pianos. One day, four children came and they all took the 20 pianos. Only Yaya suddenly calmed down and said, "We can share a point!" The aunt who sold the piano said, "Yes, I didn't think of that." Later, the star said, "How do you divide it?" Who can answer the question of the stars, Yaya said. A child named Honghong said, "I can answer that 20 divided by 4=5. So each of us can get five pianos. " Yaya, the star and the aunt said, "Great."
I went to buy stickers for my brother last night and bought eight posters. I bought a puzzle of armored soldiers. Each poster is 1 yuan * * 8 yuan, and the puzzle 3 yuan is1* * 8+3 =1yuan. I got the price for my boss, which was 65438 cheaper. My mother and I went home happily.
Interesting math story 7 When Cuomo was a middle school teacher, he forgot the product of seven plus nine in class one day. When he hesitated for a long time, a classmate said the answer was 6 1, so he wrote it down accordingly.
How do I know that another voice said he should write 69. Of course, Cuomo knew there was only one correct answer. As for 6 1, 69 or other figures, he can't decide. So he began to analyze, saying loudly that 6 1 is a prime number, not a product, 65 is a multiple of 5, and 67 is also a prime number. 69 seems too big, so the answer is 63!
Interesting story of mathematics 8 A beehive is a strictly hexagonal cylinder with a flat hexagonal opening at one end and a closed hexagonal diamond bottom at the other end, which consists of three identical diamonds. The rhombic obtuse angle of the chassis is 109 degrees 28 minutes, and all acute angles are 70 degrees 32 minutes, which is both firm and material-saving. The honeycomb wall thickness is 0.073 mm, and the error is very small.
Interesting story of mathematics 9 Red-crowned cranes always move in groups, forming a "human" shape. The angle of the herringbone is 1 10 degrees. More accurate calculation also shows that half the angle of the herringbone-that is, the angle between each side and the direction of the crane group is 54 degrees, 44 minutes and 8 seconds! And the angle of diamond crystal is exactly 54 degrees, 44 minutes and 8 seconds! Is it a coincidence or some "tacit understanding" of nature?
Interesting math story 10 It's sunny today.
My sister asked, "What should we do?" I said, "We can take out the sugar and separate it.
We kept our word and took out 20 pieces of sugar. My sister said, "Let's have one each." I said, "No, because 10×2=20, each of us has 10."
We separate the sweets and put them in different boxes.
Interesting math story 1 1 It's very hot today.
Mother said, "Why don't you write a math story alone?" I said, "Good!" My sister also said, "Good!" Mother added, "each of you will watch an episode of TV to see who writes well."
I watched Balala's Little Devil, and so did my sister.
10 minute 600 seconds per episode.
Mom said, "How long is the second episode?" I said, "10+ 10=20 minutes, 1200 seconds.
Interesting math story 12 It's the weekend again, and my mother takes me fishing (we're going to fish fake fish).
We came to Hongshi Park and fished fake fish.
The fishing stall is located on the east side of Hongshi Park. The fish pond is actually an inflatable pond with all kinds of plastic fish, ducklings, octopus, dolphins and so on. Fishing rods are also plastic. An iron ball hung under the fishing line and smashed a nail in the fish's mouth. In this way, fish can be attracted to the bait.
My sister said curiously, "Who can catch all the fish in such a big pond?" Besides, where do you put the fish after fishing? "Mom gave us two yuan and fifty cents each, and one * * * is five yuan. My sister and I started fishing with fishing rods.
However, all the fish sank to the bottom of the water. The annoying thing is that the iron ball can't sink anyway. What shall we do? So, I press the iron ball in one hand and hold the fishing rod in the other. In this way, we soon caught dolphins, octopus, tropical fish, goldfish and so on.
Later, two younger brothers came.
One of the younger brothers fished fast, but he didn't catch any dolphins.
I gave him four, and now there are only eight.
Please guess how many dolphins I have. You must have guessed, right It is 12, and the formula is: 4+8= 12 (only).
We played for about an hour and then went home.
One day, when the digital cards were having lunch together, the youngest one spoke.
Brother 0 said, "Let's take some photos together. What do you think? " 0' s brothers and sisters said in unison, "Good." Brother 8 said, "Brother 0' s idea is really good. I will be a good person once. Shall I provide camera and film for Brother 8? " Old four said, "starling, yes, it's just a little troublesome." Better use my digital camera. That's settled. "
So, they got busy. Finally, they took pictures for them and immediately sent the digital camera to the print shop. The computer sister tried to ask them for money, but who paid for it? They stared at each other one after another. This is what the computer sister said, "A ***5 yuan, a * * * eleven brothers and sisters, how much does one person pay on average?" Among the eleven of them, Lao Liu is the cleverest, and this time he is the first to work out the result. Do you know how it is worked out?
Interesting math story 14 Little Bear's mother is ill. In order to earn money to treat his mother, Little Bear gets up before dawn every day to go fishing in the river and catch up with the market to sell fish.
One day, as soon as Little Bear set up the fish stall, the fox, the black dog and the old wolf came. When the 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 grinned." 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. "Bear's face is reluctant:" I'll sell you the fish. Who will 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. To tell you the truth, Black Dog and I are very good to each other. If you buy fish heads and tails, won't you help Uncle Wolf and 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 Jin 15 yuan, fish tail 10 Jin 10 yuan. The wolf, the fox and the black dog quickly ran to the Woods with the fish, matched the fish head, the fish body and the fish tail, and then divided them equally. ...
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.
Clever students, do you know what this is all about?
Once upon a time, an old man said to his three sons before he died, "I can't do it." There are only seventeen trees in our house. After I die, the boss will be divided into half, the second child into one third and the boss into one ninth. Besides, no tree can be cut down. "With these words, the old man died.
The three brothers were very sad when they saw their dead father. So they talked about burying their father. They also discussed how to divide the tree according to father's instructions and the old man's will. They can't be separated. The three brothers are at a loss, and no one can do anything.
However, just when they were at their wits' end, a clever child passed by and solved the problem easily. Let's look at his solution.
The children and three brothers said, "If we want to use existing trees, we can't separate them according to your father's instructions, so we need to use outsiders' trees." Hearing this, the three brothers were still puzzled, so the children continued to answer questions for them.
Solution:
Add points from the neighbor's tree, 17+ 1= 18 (tree). Boss:/kloc-half of 0/8 is 9 (tree). One third of the second child: 18 is 9 (tree).
Interesting math story 16 calculator of your body
Our bodies are really great. The hand is an ordinary calculator. The most common hand is the multiple calculation of 9. Parents may not understand, but many children will soon learn. When calculating the multiple of 9, put your hands on your knees and count your fingers from left to right, as shown in the table below. Now choose the multiple of 9 you want to calculate, assuming that the multiplication is 7×9. As shown in the above picture, just bend the finger marked with the number 7. Then count the left index finger of the bent finger as 6, and the index of the left hand on its right is 3. Put them together, the answer of 7×9 is 63.
How many socks can you make a pair?
The answer to the question how many pairs of socks can be paired is not two. And not just in my house. Why is this happening? That's because I can guarantee that if I take out two socks, black and blue, from the drawer on a dark winter morning, they may never be a pair. Although I am not very lucky, if I take out three socks from the drawer, I will definitely have a pair of socks of the same color. Whether the socks are black or blue, there will be a pair of the same color in the end. In this way, with the help of one more sock, the mathematical rules can overcome Murphy's law. From the above situation, it can be concluded that the answer to "how many socks can make a pair" is three.
Of course, this is only true if the socks are two colors. If there are blue, black and white socks in the drawer, take out a pair of socks with the same color, at least four pairs. If there are 10 pairs of socks with different colors in the drawer, you must take out 1 1 pairs of socks. According to the above situation, the mathematical rule is: If you have n kinds of socks, you must take out N+ 1 to ensure that you have an identical one in Shuang Yi.
Rope burning timing
A rope, burning from one end, takes 1 hour to burn out. Now you need to use this rope and a box of matches to measure for half an hour without looking at your watch. You may think it's easy. You just need to make a mark in the middle of the rope, and then measure the time it takes for the rope to burn halfway. Unfortunately, however, this rope is not uniform. Some places are thick and some places are thin, so this rope burns at different speeds in different places. It may take only 5 minutes for half of the rope to burn, and 55 minutes for the other half to burn. Faced with this situation, it seems impossible to accurately measure 30 minutes with the rope above, but this is not the case, so we can use an innovative method to solve the above problem, that is, ignite from both ends of the rope at the same time. The rope must take 30 minutes to burn out.
The problem of train running in the opposite direction
The two trains travel in opposite directions along the same track, and the speed of each train is 50 miles per hour. When the distance between two carriages is 100 mile, a fly flies from train A to train B at the speed of 60 miles per hour. When it meets the train B, it immediately turns around and flies to the train A, and so on until the two trains collide and crush the fly into pieces. How far did the fly fly before it was crushed to death?
We know that the distance between two cars is 100 miles, and the speed of each car is 50 miles per hour. This means that each car has traveled 50 miles, that is, two cars collided one hour later. During the short time from the train to the collision, the fly kept flying at 60 miles per hour, so when the two cars collided, the fly flew 60 miles. Whether the fly flies in a straight line, along a "Z" line or rolls in the air, the result is the same.
Flipping a coin is not the fairest.
Flipping a coin is a common way to make a decision. People think this method is fair to both sides. Because they think that the probability of coins falling backwards is the same as that of coins falling backwards, both of which are 50%. Interestingly, this very popular idea is not correct.
First of all, although it is unlikely that a coin will stand on the ground when it falls, this possibility exists. Secondly, even if this small possibility is ruled out, the test results show that if you flick the coin with your thumb in a conventional way, the probability that the coin will still be up when it hits the ground is about 5 1%.
The reason why this happens is that with a flick of the thumb, sometimes the money will not turn over, but will only rise like a trembling flying saucer and then fall. If the next time you want to choose which side of the coin in the coin toss's hand is facing up, you should look at which side is facing up first, so that you have a greater chance of guessing correctly. But if that person is holding coins and turning his fists one by one, then you should choose the opposite from the beginning.
Probability of the same Amanome
Suppose you are attending a wedding of 50 people, someone may ask, "I wonder what is the probability that two people here are in the same Amanome?" The same here refers to the same Amanome, for example, on May 5th, but it doesn't mean that the birth time is exactly the same. "
Perhaps most people think that this probability is very small, and they may try to calculate it, guessing that this probability may be one in seven. However, the correct answer is that there are about two guests whose birthdays are on the same day attending the wedding. If the birthdays of this group of people are evenly distributed at any time in the calendar, the probability that two people have the same birthday is 97%. In other words, you have to attend 30 parties of this size to find a party without the same birthday.
One of the reasons why people are surprised is that they are puzzled by the probability that two specific people have the same birth time and any two people have the same birthday. The probability that two specific people are born at the same time is one in 365. The key to answer this question is the size of the group. As the number of people increases, the probability that two people will be in the same Amanome will be higher. Therefore, in a group of 10 people, the probability of two people in the same Amanome is about 12%. In a gathering of 50 people, the probability is about 97%. However, only when the number rises to 366 (one of whom may have been born on February 29th) can you be sure that the two people in this group must be the same Amanome.
Actually, math is very interesting. Everyone must be happy to learn math!
Interesting math story 17 The teacher asked a question: 8÷2=?
Then ask everyone: what is 8 divided into two halves?
Pippi replied: equal to 0!
The teacher said: how can it be?
Pippi explained: separate up and down!
Ding Ding said: No, it is equal to the ear!
Teacher: Oh?
Tintin replied: Left and right are separated!
Interesting story of mathematics 18 The teacher said: Numbers don't deceive people. If it takes 12 days for a person to build a house, then it only takes 12 people a day and only 288 people an hour.
Students said: 17280 people only need one minute, 1036800 people only need one second. In addition, if it takes six days for one ship to cross the Atlantic, it takes six ships a day. Four cups of 25-degree water add up to boiling water! Numbers don't lie!
Interesting math story 19 math story. Come on.
Two people said three words:
1 1 1=337,
therefore
Good, good, good = good.
So the multiplicand and multiplier must contain multiples of 37 and multiples of 3. But both the multiplicand and the multiplier are two digits, and the last digit is the same, so one of the two digits must be 37 or 74.
If one is 74, the last digit of the other is 4, which is a multiple of 3, so it is at least 24. but
7424 1000,
The latest interesting math story will come soon: I am not satisfied with the original formula. So it can't be 74, only 37.
In short, regardless of the order of multiplicand and multiplier, the only possible formula is
2737=999。
These three sentences represent the numbers 27, 37 and 999 respectively.
Come on! Coming! Okay, okay, okay.
Three sentences and seven words are a math problem: use these three sentences to form a multiplication formula.
During the Spring Festival of 20 years, a professional chicken farmer casually stood in the yard, counted the total number of chickens, and decided to stay, 1/2, to the People's Liberation Army 1/4, and to the nursing home 1/3. After he sent the chickens away, he heard the chickens crowing in the room, only to know that there were 10 chickens missing. So I counted the chickens inside and outside the room again, and there was nothing wrong, no more, no less, just 1/2 left. Small carelessness is strange. What's the problem? Do you know how many chickens Xiao carelessly counted in the yard?
How many guests came one day and Xiao Lin was washing dishes at home. Xiao Qiang saw it and asked, "Why do you wash so many bowls?" "
We have guests at home. ""How many people came? " Kobayashi said, "I don't know. I only know that each of them uses a rice bowl, two people share a soup bowl, three people share a vegetable bowl, four people share a big wine bowl, and one * * * uses 15 bowl. "Do you know how many guests are here?