When he was a teenager, Hua especially liked mathematics, but his math performance was not outstanding. 19 years old, an excellent article shocked the famous mathematician Xiong Qinglai at that time. From then on, under the guidance of Mr. Xiong Qinglai, he embarked on the road of studying mathematics. In his later years, for the sake of national economic construction, he popularized and applied pure mathematics to industrial and agricultural production and struggled for the construction of the motherland for life!
Grandpa Hua carefully cultivated the younger generation, so that young mathematicians can thrive and stand out. After work, he also does not forget to write some popular science books for his friends for many years. The following is an interesting math game that Grandpa Hua once introduced to his classmates:
A teacher wants to tell his three students which is smarter. He used the following methods: show them three white hats and two black hats in advance, then tell them to close their eyes, put on their hats respectively and hide the remaining two hats. Finally, tell them to open their eyes, look at other people's hats and say the color of their hats.
The three students looked at each other, hesitated for a moment, and said in unison that they were wearing white hats.
Smart reader, think about it. How do they know the color of the hat? In order to solve the above problems, let's first consider the problem of "two people 1 black hat and two white hats". Because the black hat only has 1. If I wear them, the other person will immediately say that he is wearing a white hat. But he hesitated, which showed that I was wearing a white hat.
In this way, the problem of "three people, two blacks and three whites" will be solved. Suppose I wear a black hat, then the two of them become a question of "1 two people with black hats and two white hats", and they can answer it right away, but they all hesitated for a while, which shows that I wear a white hat and the three of them have the same thinking, so they all took out their own white hats. Seeing this, the students may clap their hands and say it is wonderful.
Grandpa who came to China later complicated the original problem. How to solve the problem of "n people, n- 1 black hat and several (not less than n) white hats"? In the same way, it is easy to solve. He also warned us that being good at "retreating" complex problems, "retreating enough" and retreating to the most primitive place without losing importance are the secrets of learning mathematics well.