Zhou Wen's mother is a chemist in Yulin Cement Plant. One day, Zhou Wen came to the laboratory to do his homework. I want to go out to play when I'm done. "Wait, mom will test you on another question," she continued. "Look at these six glasses for laboratory testing. The first three are all water, and the last three are just empty. Can you just move 1 glass and separate the glass filled with water from the empty one? " Zhou Wen loves to think, and is a famous "cleverness" in the school. She just thought about it for a while and then did it. Please think about it, how does "cleverness" work?
Three boys fell in love with a girl at the same time. In order to decide which of them can marry the girl, they decided to duel with pistols. Xiao Li's hit rate is 30%, and Xiao Huang is better than him, with a hit rate of 50%. The best shooter is Kobayashi, who never makes mistakes, and the hit rate is 100%. Because of this obvious fact, in order to be fair, they decided in this order: Xiao Li shot first, Huang Xiao second and Xiao Lin last. And so on until there is only one person left. So which of these three people has the best chance to survive? What strategies should be adopted?
There are two prisoners in a cell. Every day, the prison will provide this cell with a can of soup for two prisoners to share. At first, these two people often have arguments, because one of them always thinks that the other has more soup than his own. Later, they found a way to kill two birds with one stone: one person divided the soup and let the other person choose first. In this way, the dispute was settled. However, now there is a new prisoner in this cell, and now there are three people sharing the soup. New ways must be found to keep the peace between them. What should I do?
Press: Psychological problems, not logical problems.
Put n round coins of the same size on a rectangular table. Some of these coins may not be completely on the table, and some may overlap each other; When another coin is placed on the table with its center, the newly placed coin will definitely overlap with some of the original coins. Please prove that the whole desktop can be completely covered by 4n coins.
A ball and a ruler about 2/3 of the diameter of the ball. How do you measure the radius of the ball? There are many ways to see who is smarter.
Five one-dollar coins of the same size. Require two-phase contact, what should I say?
8 guess the card problem
Mr. S, Mr. P and Mr. Q know that there are 16 playing cards in the desk drawer: hearts A and Q, 4 spades J, 8, 4, 2, 7, 3 flowers K, Q, 5, 4 and 6 diamonds A and 5. Professor John chooses a card from 16 card, tells Mr. P the number of points in this card, and tells Mr. Q the color of this card. At this time, Professor John asked Mr. P and Mr. Q: Can you infer what this card is from the known points or colors? So, Mr. S heard the following conversation: Mr. P: I don't know this card.
Mr q: I know you don't know this card.
Sir: Now I know this card.
Mr. Q: I know that, too.
After listening to the above conversation, Mr. S thought about it and correctly deduced what this card was.
Excuse me: What kind of card is this?
A professor who teaches logic has three students, all of whom are very clever!
One day, the professor gave them a question. The professor put a note on everyone's forehead and told them that everyone had written a positive integer on the note, and the sum of some two numbers was equal to the third! Everyone can see the other two numbers, but not his own.
The professor asked the first student: Can you guess your own number? Answer: No, ask the second, the third, the first, the second, the third: I guessed right, it was 144! The professor smiled with satisfaction. Can you guess the numbers of the other two?
10 A car hit someone and ran away in a city.
There are only two colors of cars in this city, blue 15% and green 85%.
Someone saw it at the scene when it happened.
He testified that it was a blue car.
However, according to the on-site analysis of experts, the possibility of correct conditions at that time was 80%.
So, what is the probability that the car that caused the accident is a blue car?
1 1 A man has 240 kilograms of water, and he wants to transport it to the arid area to make money. He can carry up to 60 kilograms at a time, and he needs to consume 1 kilogram of water per kilometer (even if it is water consumption). Assuming that the price of water is zero at the place of departure, it is directly proportional to the transportation distance (that is, 10 km/0 yuan/kg, 20 km/kg/20 yuan ...), and assuming that he must return safely, how much money can he earn at most?