Earlier, there were two great French mathematicians, one named bhaskar and the other named Fermat. Pascal knew two gamblers and they asked him a question. They said that after they made a bet, it was agreed that whoever won the first five games would get all the bets. After gambling for a long time, A won four games and B won three. It's getting late, and they don't want to gamble any more. So, how should this money be divided? Do you divide the money into seven parts, four for those who win four games and three for those who win three games? Or because the first time I said five innings, no one arrived, so one person got half? Neither of these points is correct. The correct answer is: the person who wins four games gets 3/4 of the money, and the person who wins three games gets 1/4 of the money. Why? Suppose the two of them bet another game, and either A wins or B wins. If A wins five games, all the money should go to him. If A loses, that is, A and B win four games each, and the money will be divided equally. Now A's winning or losing probability is 1/2, so his money should be 1/2×1/2×1/2 = 3/4. Of course, B should get1. Through this discussion, an important concept in probability theory-mathematical expectation began to take shape. Among the above problems, mathematical expectation is an average, that is, how to calculate the uncertain money in today's future. This requires multiplying the money that A may get by the winning or losing probability of 1/2, and then adding them up. Probability theory has developed since then, and today it has become a very widely used subject. Earlier, there were two great French mathematicians, one named bhaskar and the other named Fermat. Pascal knew two gamblers and they asked him a question. They said that after they made a bet, it was agreed that whoever won the first five games would get all the bets. After gambling for a long time, A won four games and B won three. It's getting late, and they don't want to gamble any more. So, how should this money be divided? Do you divide the money into seven parts, four for those who win four games and three for those who win three games? Or because the first time I said five innings, no one arrived, so one person got half? Neither of these points is correct. The correct answer is: the person who wins four games gets 3/4 of the money, and the person who wins three games gets 1/4 of the money. Why? Suppose they bet another game, and either A wins or B wins. If A wins five games, all the money should go to him. If A loses, that is, A and B win four games each, and the money will be divided equally. Now A's winning or losing probability is 1/2, so his money should be 1/2×1/2×1/2 = 3/4. Of course, B should get1. Through this discussion, an important concept in probability theory-mathematical expectation began to take shape. Among the above problems, mathematical expectation is an average, that is, how to calculate the uncertain money in today's future. This requires multiplying the money that A may get by the winning or losing probability of 1/2, and then adding them up. Probability theory has developed since then, and today it has become a very widely used subject. Earlier, there were two great French mathematicians, one named bhaskar and the other named Fermat. Pascal knew two gamblers and they asked him a question. They said that after they made a bet, it was agreed that whoever won the first five games would get all the bets. After gambling for a long time, A won four games and B won three. It's getting late, and they don't want to gamble any more. So, how should this money be divided? Do you divide the money into seven parts, four for those who win four games and three for those who win three games? Or because the first time I said five innings, no one arrived, so one person got half? Neither of these points is correct. The correct answer is: the person who wins four games gets 3/4 of the money, and the person who wins three games gets 1/4 of the money. Why? Suppose they bet another game, and either A wins or B wins. If A wins five games, all the money should go to him. If A loses, that is, A and B win four games each, and the money will be divided equally. Now A's winning or losing probability is 1/2, so his money should be 1/2×1/2×1/2 = 3/4. Of course, B should get1. Through this discussion, an important concept in probability theory-mathematical expectation began to take shape. Among the above problems, mathematical expectation is an average, that is, how to calculate the uncertain money in today's future. This requires multiplying the money that A may get by the winning or losing probability of 1/2, and then adding them up. Probability theory has developed since then, and today it has become a very widely used subject. A man was walking in the forest when he suddenly met a hungry tiger. The tiger roared and jumped up. He ran away as fast as he could, but the tiger ran after him. He kept running until the tiger pushed him to the edge of the cliff. Standing on the edge of the cliff, he thought, "It is better to jump into the cliff than to be caught by a tiger and killed alive. Maybe there is still a chance. " He jumped into the cliff and was very lucky to get stuck in a tree. That is a plum tree that grows on the edge of the cliff, and the tree is full of plums. Just as he was happy, he heard a huge roar from the depths of the cliff. He looked at the bottom of the cliff. It turned out that a fierce lion was looking up at him. The lion's voice made him tremble, but he thought, "The lion and the tiger are both the same beasts, and they eat the same things." Just put down the heart, and heard a voice. I looked carefully, and two mice were biting the trunk of a plum tree. He was in a panic for a while, and then he was relieved immediately. He thought, "It's better to be killed by a mouse than by a lion." When his mood calmed down, he saw that the plums were just right, so he picked some and ate them. He felt that he had never eaten such delicious plums in his life. He found a triangular branch to rest, thinking, "Since you are going to die sooner or later, you might as well have a good sleep before you die!" " So I leaned against the tree and fell asleep. When he woke up, he found that the black and white mouse was gone, and so were the tiger and lion. He climbed the cliff carefully along the branches and finally got out of danger. It turned out that while he was sleeping, the hungry tiger couldn't help it and finally roared and jumped off the cliff. The black and white mouse heard the tiger's roar and ran away in panic. The tiger who jumped off the cliff and the lion under the cliff fought fiercely, and both of them escaped with injuries. Truth: There will be many dangers in life, and difficulties and dangers are as inevitable as death. Since it is inevitable, it is better to relax and enjoy what you have now, and you will enjoy the sweet fruit of life inadvertently. I am in a hurry. Logo, you HK, you mushroom. Oral flies are very hard and pitiful. The woman in the Railway Bureau thought that I forced me to go to Lhasa with 1 hee hee, and dawdled on JS nuts to review the data recorded in Polan. Mother-in-law skr is my mother-in-law's daughter. Ji Guang fights and chases you. 1 Oh, mine clearance overflowed raise and boasted that the base was highly toxic.