my scientific age

Chapter 35 The first lesson of school

The sun is rising in the east, the weather is sunny, and it seems that today is a good weather.

At 10:[-] in the morning, Yu Hua, who had just finished his morning exercises, was sitting in his seat, holding a pen in his right hand, and chewing on a hard grain bun with his left hand. He stared at the desktop and turned to the mathematics book in the chapter of probability and statistics. He used [-] minutes before class to study.

Yesterday, I mastered the counting principle of probability, and the progress has just arrived at the permutation and combination.

Definition of arrangement:
Take m (m≤n, m and n are natural numbers) elements from n different elements arbitrarily, and arrange them in a column according to a certain order.

Definition of combination:
Take any m (m≤n) elements from n different elements and form a group.

The difference between the two: Arrangement is related to the order of elements, while composition has nothing to do with the order of elements.

"The meaning of permutation is to extract M elements from N elements for cooking, and permutation is to extract M elements from N elements for cooking and learning. The former has the same purpose, and the latter has different purposes. It's good, hey, what do I want? Take dry rice as an example..." Yu Hua took a bite of the dry multi-grain steamed bun, which was not very tasty when it was cold, but it was better at filling his stomach. Looking at the definitions and judgments of the arrangement and combination, he quickly understood the meaning.

I have to say that meals without oil and water are really not satisfying. The staple food for breakfast is multi-grain steamed buns and wotou, the same style as yesterday's dinner. The side dishes are pickles and pickled Chinese cabbage.

In short, no oil or water at all.

After sleeping until midnight last night, Yu Hua woke up once hungry.

After breakfast today, Yu Hua kept his mind and asked for an extra steamed bun. Then, led by the school's physical education teacher, he ran morning exercises to exercise like the students of later generations.

After the run, Yu Hua just sat down when his stomach began to croak, so he quickly took out the steamed buns left over this morning to satisfy his hunger.

"Here, Yu Hua, here's something good for you." Zhou Yuan, who had just sat down, saw Yu Hua was nibbling on a cold steamed bun, and immediately took out a love tin box with a delicate light red package from the drawer, opened the lid, and took The two long golden objects shouted at Yu Hua and handed them over.

Hearing Zhou Yuan's shout, Yu Hua raised his head, a little puzzled, and looked at two things that looked like little yellow croakers: "This is?"

"You'll know when you open it." Zhou Yuan smiled.

Putting the steamed bun in his mouth and biting it, Yu Hua freed his left hand and took the two pieces handed by Zhou Yuan, weighing about two taels, picked up one of them, and peeled off the golden wrapping paper, which was a piece of black chocolate.

"I'm a fairy, chocolate?"

Yu Hua's eyes widened immediately, and his right hand subconsciously took off the steamed bun in his mouth, not because he had never seen the world, but because the thing in his hand was too rare.

As for the price?

As an imported product from the West, chocolate that belongs to the ranks of imported foods is completely a high-end food that aristocrats exist in it, and a box of [-] grams of chocolate costs at least ten yuan.

Even if this thing is expensive, the most important thing is that you can't buy it.

Feeling the ambition of Japan's aggression, the National Government listed sugar as one of the strategic materials, and major cities across the country could no longer buy sugar, let alone chocolate that was even more advanced than sugar.

The two pieces of chocolate in his hand, which are about two taels, can cost at least five oceans.

Darling, what kind of wealthy family is this tablemate Zhou Yuan, and if you shoot it, you will get two pieces of chocolate.

Zhou Yuan smiled and said, "Yu Hua is very knowledgeable. This is American Hershey chocolate. My sister brought me back from the United States this year. Try it."

"Okay, if that's the case, then I'm welcome."

Hearing Zhou Yuan's remarks, Yu Hua didn't pretend to put it in his mouth. The taste was mellow and slightly bitter, sweet and bitter, and contained a lot of calories.

In terms of specific heat, these two pieces of chocolate in his hand can shake the half-eaten steamed buns for ten streets.

"How does it taste?" Zhou Yuan asked with concern when he saw Yu Hua's delicious food.

Yu Hua ate the chocolate and took advantage of the gap between chewing: "It's a bit bitter, but very fragrant, aren't you hungry?"

"No, I don't like the bitter taste in it very much. Just get used to it. I'm going to read." Zhou Yuan shook his head, although he knew that chocolate was a good thing, but he just couldn't get used to this foreigner's stuff. Yu Hua was happy to eat it. , then turned back to read the book.

After eating this piece of chocolate in two or three times, the hunger in the abdomen disappeared in an instant. Yu Hua ate the remaining half of the steamed bun again, glanced at the remaining piece of chocolate, and put it directly in the drawer, waiting for the next time when I was hungry. .

Putting away the chocolate, he looked up at Zhou Yuan, who was concentrating on his studies. Yu Hua silently wrote down the love of this chocolate. It is a friendship that people give you to eat, and it is a duty not to give it.

Now that you have eaten, you have to remember that no matter whether others care about it or not, whether they need your affection or not.

Not hungry, and high-calorie chocolate as an energy supplement, Yu Hua read the book again, his mind was clear and thorough, and the effect of understanding was extremely fast. The reading efficiency was suddenly much higher than when he was hungry, and he was quickly immersed in it.

Today is the eighth day of the first lunar month, Thursday.

According to the schedule formulated by the school, eight classes are required every day, four classes in the morning, four classes in the afternoon, and evening self-study from 07:30 to [-]:[-].

The first class in the morning is math, Mr. Ren's class.

"Boom! Boom! Boom!" As the time came to eight o'clock, the school rang a low and distant bell, penetrating all over the school, reminding the class time.

"Huh...fortunately, I'm almost finished learning permutations and combinations. Probability and statistics are difficult to say, and it's not difficult to say that it's not difficult. As long as you master the principles of addition and multiplication, it will be easy." After studying the book, I thought silently in my heart.

Outside the classroom door, two figures appeared, one was Mr. Ren Luo Wenguang, and the other was an unfamiliar young man in Western attire, wearing glasses and full of energy.

"The teacher is here." Squad leader Li Fan immediately shouted when he saw the figure of the successor.

All the students in the first class of science immediately put down all the affairs in their hands, sat down in a proper manner, and showed respect.

Immediately afterwards, Mr. Level Ren Luo Wenguang was in front, and the unfamiliar youth in suits was behind, and the two entered the classroom one after another and stepped onto the podium.

"What the hell?!" In the crowd, Yu Hua looked at the young man behind Mr. Successor who was a little unsteady, and was suddenly stunned, a little confused, and almost didn't swear.

This young man is none other than Hua Luogeng whom he met eight days ago!

Isn't Hua Luogeng in Tsinghua University, why did he come to Peking No. [-] Middle School?

What's going on here.

No one answered the question in Yu Hua's mind.

"Stand up." Squad leader Li Fan shouted immediately after Luo Wenguang and Hua Luogeng stepped onto the podium.

Immediately afterwards, all the students stood up, facing the two of them, with their bodies straight.

"Respect teacher."

"Hello sir."

Yu Hua and a group of students bowed to Mr. Ren and Hua Luogeng, and greeted them with respect.

"Well, everyone, sit down."

Mr. Ren Luo Wenguang nodded in response, arranged for everyone to sit down, looked around, and said, "Today, the first lesson of the school, the school specially invited Mr. Hua Luogeng, a professor of mathematics at National Tsinghua University, to teach students, this is what you are waiting for. Opportunities must be cherished, the squad leader needs to be disciplined, all students need to be serious and keep quiet.”

(End of this chapter)