Chapter 379 Qin Huaidao took the small notebook and looked at it carefully, it was clearly recorded, and it was written that Liu Xiaoyi was set up by those people.

"Those bastard boys were deliberately pointed out, and that person said that he heard Liu Xiaoyi say that he was my cousin, so he couldn't get used to it, so he pit Liu Xiaoyi. How credible do you think it is? Qin Huaidao stared at Yu Chi Baolin and asked.

"Zero!" Yu Chi Baolin said with a smile, Qin Huaidao nodded and sat down.

"Who's behind it? Can't find out? Qin Huaidao turned his head to look at Yu Chi Baolin and asked.

"I can find out, but it will take time, but now it depends on what they do next, and it may be faster." Yu Chi Baolin said to Qin Huaidao.

Qin Huaidao sat there and thought about it for a while, then turned his head to look at Yu Chi Baolin and asked, "Then tell me, is it aimed at me or Liu Pingzhong?" ”

"You are more likely, after all, Liu Pingzhong has no value, and if you want to bring him down, you need your nod, and there is nothing wrong with Liu Pingzhong in this way, it is not a wise choice to do so, I also thought about this yesterday, I guess I don't want to bring you down, but there are other purposes." Yu Chi Baolin turned her head and explained to Qin Huaidao.

"Other purposes? What purpose? Qin Huaidao then asked.

"I don't know about this, after all, now they have just made a move, but, in terms of means, it looks like someone from the family did it." Yu Chi Baolin looked at Qin Huaidao with a smile and said,

As soon as Qin Huaidao heard that he was from the family, he immediately understood what was going on.

After a while, Yu Chi Baolin went back, while Qin Huaidao sat down and thought about it for a while.

In the morning, Qin Huaidao still went to the university, and didn't care about Liu Xiaoyi's affairs at all, and now he also needs to suffer a little, he still has classes today, Qin Huaidao took the lesson plan, and when he arrived at the classroom, he just arrived at the classroom, Qin Huaidao found that the class of 300 people was full of four or five hundred people, and it was stuffy.

"Are there so many people in the arithmetic class?" After Qin Huaidao entered, he said with a smile, and at the same time looked at the young people sitting here, most of them were older than him, and Qin Huaidao looked at the elderly, maybe more than 30 years old.

"I've seen sir!" Those students saw Qin Huaidao standing on the podium, so they stood up and bowed to Qin Huaidao, they all knew how this university came about, and they also knew that they were able to study here because of Qin Huaidao, so those students saw Qin Huaidao, and they were all respectful.

"Hello students, please be seated! Today we will talk about the use of arithmetic, that is, in our lives, we need to use arithmetic, from the small ones you buy on the street to the accounting of various departments of Datang.

However, the cost-effectiveness of each department is not the largest, nor is it the most complicated, and I would like to ask you, which of you can calculate the circumference and area of a circle? This question was calculated more than 100 years ago, who knows? Qin Huaidao sat there, looked at them and asked with a smile,

The students were all watching him silently.

"Nobody knows?" Qin Huaidao looked at them with a smile, and they still looked at Qin Huaidao quietly.

"Well, what about the area of the triangle?" Qin Huaidao looked at them with a smile and asked.

"What about the area of the trapezoid? You know what a trapezoid, right? Qin Huaidao said and took out a blank piece of paper, with a trapezoid drawn in advance, those students still look at me, I look at you!

"Well, it seems that you know very little about arithmetic, but arithmetic is actually the most important subject in all disciplines, and without arithmetic, the country will not have a way to develop.

I'll give you an example, if we want to build a bridge, we need to calculate the load-bearing on the bridge, the pressure of the side flood resistance, after the calculation, we also need to calculate how deep the foundation needs to be built, what materials are used, in order to ensure that the bridge is completely correct under most conditions.

In addition, to build a tall tower, it is necessary to calculate the load-bearing of the foundation below, and how deep and thick the foundation needs to be laid.

In addition, it is a matter of random queuing, which is also related to the military, which involves the problem of probability, in short, if you learn arithmetic, many problems in the world can be solved with mathematics! Qin Huaidao then looked at them with a smile and said.

"Can it all be solved? Then I would like to ask, if a person is sick, how to solve it? At this time, one of the students stood up.

"Haha, that's a good question, let's discuss it, let's just say that a person is sick, how can we solve it with mathematics, for example, I'll just say a very common disease, a cold! The most ordinary! Right? Qin Huaidao heard the student's question and asked with a smile, and the students nodded.

"Medication and other treatment methods for colds, for example, with the first medicine, sixty percent of people can be cured, with the second medicine, five adults can be cured, with the third medicine, four adults can be cured,

At the same time, without medicine, there are two percent of the cure, if you drink hot water there are three adults cured,

So let me ask you two questions, how to determine this ratio? For example, two adults are cured without taking medicine? Second, if I take the first medicine and the third medicine at the same time, how many more adults will be cured? Qin Huaidao looked at them with a smile and asked, they look at me, I look at you.

Then one of the students stood up and asked, "Sir, isn't that what you said?" ”

"Haha, that's what I said, I want to ask you now, if this thing is true, then how to be sure that this is almost true and is an accurate data?" Qin Huaidao then looked at those people and asked.

"This, you need to count, right?" Another student spoke.

"That's right, counting, that is, counting, among these treatments, there are 100 people in each of these treatments, give them medication, and count how many people are cured after five days!

And the second question I asked, the same, recruit 100 people, use two drugs at the same time, and see how effective they are.

If their cure rate is less than 60%, then it means that the effect of simultaneous medication is not good, and it is better to use drugs alone, but if the cure rate exceeds 60% and reaches 80%, is it better to combine drugs? Qin Huaidao then looked at them and asked,

The students all nodded.

"Arithmetic, it seems that it has nothing to do with curing, but it has a lot to do with it, it is designed to be statistical, and I will ask you a question, for example, let's talk about the farmland outside Chang'an City, if the farmland in Chang'an City has 100,000 mu, let me ask you, how many voles are there in these 100,000 acres of fertile land?" Qin Huaidao looked at them with a smile and asked,

Those students heard, you look at me, I look at you, I don't know why you have to count the number of voles.

"Sir, if we want to count, it's not easy to get it, we have to dig all those vole holes to know, and 100,000 acres!" One of the students stood up and asked.

"And it's useless to know!" Another student took over.

"Why is it useless, I know that there are many voles, damage the dealer, it is time to start in advance, you know that voles are very fecund, once they are not eliminated this year, their number will be several times higher next year, and the food in the farmland is not enough for them to eat!" Qin Huaidao looked at them with a smile and asked.

"Do you know how many litters voles breed a year, how many litters there are, and how long it takes for voles to breed?" Qin Huaidao then asked them,

Qin Huaidao just wanted to arouse their interest in learning mathematics, so they looked at Qin Huaidao.

"Voles have a strong reproductive ability, a female mouse produces 6 to 8 litters per year, each litter, and young rats can give birth in 2~3 months.

I will give birth to 6 litters a year according to a female mouse, and a litter is to give birth to 10, 5 males and 5 females, and start giving birth in three months.

Let me ask you, just a pair of voles, after a year, how many offspring will there be, and how threatening are these offspring?

Suppose they eat 10 catties of grain a year, do you calculate, how much food does a pair of voles and their offspring need to eat? Qin Huaidao continued to ask them,

Those students, you look at me, you look at you.

"This data is a bit complicated to calculate, let's calculate that they give birth to one litter a year, not 6 litters, otherwise, you don't understand the way of calculation,

The first pair gave birth to 10, and after 3 months, 10 adults were able to give birth to 50, and after another three months, it was 250, and in another three months it was 1250.

If this is based on the fact that they produce one litter a year, this data is 1560 offspring, plus the previous pair, it is 1562, and if you count them giving birth to 6 to 8 litters, think about how much this data is? How much food can be consumed in a year?

A pair of voles and their offspring, enough food to feed 100 of us here in a year, is a pair of voles! Qin Huaidao looked at them and said.

"Oh my God?"

"So powerful?"

"This, you can't keep voles, I said, my family, every winter to dig vole holes, there are a lot of them, no matter how you get rid of them!" ...

The students were there and they were talking.

"Therefore, it is meaningful to count how many voles there are in 100,000 acres of land, and it can be predicted that a year later, if no measures are taken, I think that the grain of these 100,000 acres of fertile land will be harvested, and you also know that voles have the habit of storing grain!" Qin Huaidao looked at them with a smile and said, they all nodded.

"What is the way of statistics? 100,000 acres of land, dig it all up? Qin Huaidao looked at them with a smile and continued to ask, they look at me, I look at you.

"Sampling, the best way is to take samples, and then count, calculate how many voles there are in the entire 100,000 acres of land,

For example, in each area, randomly take 10 points, 10 acres of land at each point, dig, dig voles, count how many voles, and then add up and divide by 100, you can calculate how many voles there are in an acre, and then multiply by 100,000 to know how many voles are in the entire 100,000 acres! It's not exact, but it's not that much different! Qin Huaidao stood there, looked at them and said with a smile.

"Sir, what is sampling?" At this time, a student stood up and asked, and the other students were also staring at Qin Huaidao,

Seeing this, Qin Huaidao knew that his goal had been achieved, which aroused their interest in arithmetic.

In this era, if you want them to learn arithmetic, and arouse their interest, otherwise, they really won't learn it.

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