Mathematical problems of Olympic math brain teaser 1
1. There is an electronic clock that rings every hour and lights up every 9 minutes.
At noon 12, ring and light.
When is the next bell and light?
Answer: 3 pm.
Reason: First of all, the bell should ring at the hour. Secondly, the time interval must be a multiple of 9, so you can choose ... minutes from 60, 120, 180.
So the next time should be 180 minutes, which is 3 o'clock.
2. Spell 1-70 1=2 with a matchstick, and move a matchstick to make the equation hold.
Answer: 1 plus the minus sign on 1 = 2...7.
3. When is 5 greater than 0, 0 greater than 2, and 2 greater than 5?
Answer: 5 is cloth, 0 is stone and 2 is scissors.
4. An officer made 24 soldiers stand in 6 rows, with 5 people in each row. Soldiers are all stupid.
The last soldier finally came up with a good idea.
How did he arrange it?
Answer: Just arrange in a hexagon.
5. How many eggs are there in a dozen?
Answer: 0, because it is broken.
6. Xiao Qiang was only six points short of passing math, and Xiaoming was only six points short of passing math, but Xiaoming and Xiao Qiang got different scores. Why?
Answer: One is 54 points and the other is 0 points.
7. There is a book that both brothers want to buy.
If you buy it with your brother's bill, you will lack 5 yuan; If you buy it with your brother's. Money, you will be short of 1 cent; If you add up the money and buy only one book, the money is still not enough.
So what's the price of this book?
Answer: The price of this book is 5 yuan.
My younger brother has no money, and my younger brother only has 90 cents in 4 yuan.
8. 1=5
2=25
3=75
4=2435
Q 5=？
Answer: 5
9. Mrs. Wang and Mrs. Li went shopping in the mall, but they didn't bring enough money. Mrs. Wang's money and Mrs. Li's money add up to buy clothes, which is 30 yuan more. Mrs. Li's money and Mrs. Wang's money add up to buy shoes, which is more 100 yuan. Clothes cost twice as much as shoes. How much money did Mrs. Wang and Mrs. Li bring together?
Answer: After buying clothes, there is more 30 yuan, and when buying shoes, there is more 100 yuan, so the money for clothes more than shoes is (100-30)=70 yuan.
I also know that the price of clothes is twice that of shoes, so the extra price is the price of shoes.
So Mrs. Wang and Mrs. Li brought 70+ 100 = 170 yuan.
10. 1? Arrive? 100? 100, how many? 9? Words?
Answer: 20 9s.
11.12m long rope tied1puppy to the trunk. Although the puppy greedily looks at the L bones 2 1 m away from it, it can't reach them. Excuse me, how should a puppy grasp a bone?
Answer: Turn around and grab it with your hind legs.
12. A man was born in 10 BC and died in 10 AD, the day before his birthday. How many years did this man live when he died?
Answer: 19
13. Xiao Li takes the elevator to the14th floor. It took 60 seconds, but it took him five minutes to go downstairs without stopping. What happened?
Answer: Go upstairs and take the elevator and go downstairs and take the stairs.
14. Just now, he said that he could fly 65,438+10,000 kites at a time. He didn't brag.
Do you know what he said?
Answer: Write 100,000 on the kite.
15. Which year is the same as reading backwards?
Answer: 196 1 year.
16. How many heads does a rope have?
Answer: 4
17. There are 12 lighted candles on the table. First three were blown out by the wind, and then two were blown out by the wind. How many candles are left on the table?
Answer: 12.
18. There are three people in a photo, but there are two fathers and two sons. Why?
Answer: The people in the photo are grandpa, dad and son.
19 and 10 people are playing hide and seek. Four people have been found. How many people haven't been found?
Answer: 5
20. A person bought a chicken for 8 yuan, sold it for 9 yuan, and then felt that it was not worthwhile. He bought it back at 10 yuan and sold it to another person at 1 1 yuan.
Ask him how much money he earned.
Answer: 2 yuan.
Math problem 2 of Olympic math brain teaser
1. Iron mouth, loves to eat paper, and specializes in doing good deeds for people. Press it on your nose and it will bite. After biting off an iron tooth (hitting office supplies), answer: stapler.
2. A bird killed one, but why didn't the other nine fly? Answer: Because it is a group of ostriches.
3. How much are three hearts worth? Answer: 200 million
4. After graduation (name a holiday) Answer: National Day.
5. Stone should stand out, don't guess the right word (type a word) Answer: stone.
6. What animal do students like to marry best? Answer: mouse.
Xiao Ming ran for ten minutes in the wilderness of heavy rain. Why is his clothes wet and his hair not? Answer: Xiao Ming is bald.
8. Young and ignorant (make a place name in Hubei) Answer: Dawu
9. The thousand-layer treasure house is opened, and it is dark and vertical and horizontal. It records the events of past dynasties, without which knowledge cannot be spread. Answer: books.
10. Sunflowers are really strange. It's open in the sea, and its color is good or not. Small fish and shrimp is its dish (killing an animal) answer: anemone.
1 1. Under what circumstances will a person become a chicken? Answer: When it rains.
12. Put down a sentence with a sullen face (three-character qq space language) Answer: Message board.
13. Resume (typing an ancient work) A: Zhu Nian
14. Wearing two coral trees and a plum blossom suit, four legs are slim and vigorous, but they run as fast as the wind (killing an animal) Answer: sika deer.
15. See you in September? Exhibition wing lattice (playing a scenic spot in Jiangsu) answer: mysterious view
16. There are two places on the earth. Yesterday can be today, and today can be tomorrow. Where is that place? Answer: South Pole and North Pole.
17. Don't take your notes when you speak (play a sport) Answer: Karate.
18. A pot of porridge, 10,000 yuan (five-word idiom) Answer: Things are rare.
19. Check one by one (type a word) Answer: apricot.
Everyone takes part in the rectification movement (in a popular word) A: Policy.
Math question 3: A brain teaser in Olympic Mathematics
1. Suppose 1=5 2=6 3=8 4=7 5=?
Answer: 1
2. A tailor has a piece of woolen cloth, which is16m long. She cuts 2 meters from it every day and asks how many days later, she cuts the last piece of woolen cloth.
Answer: (8- 1)=7 (days)
3.a b c + c d c = a b c d
How much is abcd?
Answer: a= 1 c=9 d=8 b=0.
109+989= 1098
4. Ali said that under certain conditions, 4- 1=5, and said that Xiaoying can prove the correctness of this method by graphic means. After Ali produced the evidence, she had nothing to say. How did Ali prove the test? Guess.
Answer: A table with four corners has five corners after cutting off one corner with a knife.
5. The price of each bottle of soda is 1.00 CNY, and every two empty bottles can be directly exchanged for 1 bottle of soda. If you buy soda with 20.00 CNY, how many bottles can you drink?
Answer: 1. Buy 20 bottles, drink 20 bottles, and empty 10 bottles (20).
2.20 Empty bottles are 10 bottles, drinking 10 bottles and empty 10 bottles (10).
3. 10 5 bottles for empty bottles, 5 bottles for drinking, 5 bottles for empty bottles (5)
4.5 Empty bottles for 2 bottles, drink 2 bottles and empty 3 bottles (2)
5.3 Empty bottles are 1 bottle, drink 1 bottle and empty 2 bottles (1).
6.2 Empty bottles are 1 bottle, 1 bottle, and empty bottles are 1 bottle (1).
7. Borrow 1 empty bottles, a total of 2 empty bottles, and replace them with 1 bottles and others (1).
Total: 20+10+5+2+1+1= 40 bottles.
6. 1-70 1=2 spelled with matchsticks. Move a matchstick to make the equation hold.
Answer: 1 plus the minus sign on 1 = 2...7.
7. When is 5 greater than 0, 0 greater than 2, and 2 greater than 5?
Answer: 5 is cloth, 0 is stone and 2 is scissors.
8. An officer made 24 soldiers stand in six rows, each with five people. Soldiers are all stupid.
The last soldier finally came up with a good idea.
How did he arrange it?
Answer: Just arrange in a hexagon.
9. How many eggs are there in a dozen?
Answer: 0, because it is broken.
10. A person bought a chicken for 8 yuan, sold it for 9 yuan, and then thought it was not worthwhile. He bought it with 10 yuan, and bought another one with 1 1 yuan. How much did he earn?
This is a question:
There are three algorithms:
1. At first, there was only 8 yuan, and finally you had 1 1 yuan, so you earned 3 yuan;
2. The first time the protagonist lost 8 pieces, and the second time he got a chicken; The hero gets 9 pieces and loses a chicken; On the third sale, the hero lost 10 and got a chicken. In the fourth transaction, the hero got 1 1, and one chicken was missing, so the total GDP was 8+9+10+1= 38 yuan +4 chickens.
There are three transactions in the whole event. Let's see which three deals are specific.
The first transaction: 8 yuan buys, 9 yuan sells, and gains 1 yuan;
The second transaction: 9 yuan sells, 10 yuan buys, and the profit is-1 yuan;
The third transaction: 10 yuan buys, 1 1 yuan sells for profit 1 yuan;
The whole process:1-1+1=1yuan.
So the analysis shows that this person is a fool, because the last two transactions are equal to nothing.