The eldest princess nodded slightly, she was able to calculate that the answers to the first two questions were not because she found a way to solve them, but because she calculated them by force.

It's just that she has a quick mind, and the speed at which she calculates this question is far more than anyone else.

Jiang Han said: "For example, if you want to solve the problem of chickens and rabbits in the same cage, there are several solutions. ”

After a pause, he said, "The first method is to put thirty-five heads on the top and ninety-four feet on the bottom. Half of its feet, get forty-seven, to reduce more from less, and then order, three by four, five by seven, one by three, two by five, that is, the number of pheasants. ”

With Princess Ningyue's intelligence, she immediately understood this solution, revealing a look of sudden enlightenment.

The maidservant beside her, Qingfeng, was still frowning and thinking.

Jiang Han said: "In addition, there is another simpler solution, the first row is thirty-five, the second row is ninety-four, and then divide the number of feet by two, use the number of heads to subtract the number of feet, and use the remaining number to subtract the number of heads." Then the first row is the number of pheasants, and the second row is the number of rabbits. ”

These two algorithms are mentioned in the "Sun Tzu Sutra of Calculations", and they are also the solutions that the ancients came up with.

Jiang Han continued: "As for the second question, there is this solution, which is enough to reduce the head, and the remaining half is the beast; With four multiplied beasts, reduce the full, and the remaining half is the number of birds. ”

Princess Ning Yue's eyes lit up, such a solution is too subtle and too smart!

It's hard to imagine, how did Jiang Han figure out this solution?

After all, Princess Ning Yue was smart and realized when she touched it, while Qingfeng was in a daze when she heard it, and she hadn't reacted from the first solution.

She looked at the eldest princess, and then at Jiang Han, she was even more confused.

I haven't understood yet, so you're done?

There is a sense of déjà vu that the scumbags can't keep up with the learning speed of the school bully.

These solutions are just appetizers, and the next thing is the shocking thing! Jiang Han said: "Although these solutions are wonderful, there are some difficulties after all, those who have arithmetic talent can understand it as soon as they hear it, and those who do not have arithmetic talent need to understand it for a long time. ”

Hearing this, Princess Ning Yue looked at Jiang Han, her beautiful eyes flashed, and the children could understand it? Can you also solve the answer? This is a bit magical, even a little fantastical!

"Childe's words made Bengong curious, what is the solution, even children can solve the answer." Ning Yue said softly.

Jiang Han raised his eyebrows and said, "Her Royal Highness the princess doesn't want to believe it? ”

Ning Yue said: "It's amazing. ”

Jiang Han smiled, the next thing he wants to talk about is equations, this method may not be the best to use, but it must be the easiest to learn, even if it is a child, as long as he knows how to list equations and set unknown numbers, he can easily solve the problem of chickens and rabbits in the same cage, and he can solve it without even looking at the problem, just looking at the numbers.

He wants to give the eldest princess a little shock!

But before he gets to the equations, he wants to add to that sense of shock.

So, Jiang Han shouted: "Zhou Hu, take a pen and paper." ”

"Yes, young master!" Outside the courtyard, Zhou Hu responded, and soon took the four treasures of the study room and placed them neatly on the stone table in the courtyard.

Jiang Han came to the stone table, picked up the brush, dipped it in ink, and wrote quickly on the paper.

Princess Ning Yue raised her eyes and looked, there were several arithmetic problems on the paper, which were similar to the chicken and rabbit cage problem.

Question 1: "Today there are those who do good deeds and those who do not do good deeds do sixty steps." Today, those who do not do good deeds will take a hundred steps first, and those who do good deeds will chase after them, and ask how many steps can they reach?"

Question 2: "There are nine pieces of gold and eleven pieces of silver, and they weigh them in a moderate proportion." Trade one of them, gold light thirteen taels. Q: How much does gold and silver weigh in one piece?"

Question 3: "Four horses and six oxen, a total of forty-eight taels; Three horses and five cows, with a total price of 38 taels, ask what is the price of horses and cattle?"

These three questions are very tricky and weird!

Before, the eldest princess needed to think carefully for a long time if she wanted to solve the answer, but after coming into contact with the method Jiang Han said, it was not difficult to solve it.

The eldest princess looked up suspiciously, looking at Jiang Han, not knowing his intention in writing these three questions.

Jiang Han said: "Your Royal Highness the eldest princess, believe it or not, as long as this Qingfeng girl listens to my lecture for half an hour, she can easily learn arithmetic and solve the three questions on this paper!" ”

No way!

When pigs fly!

This is what the eldest princess subconsciously wants to say.

Although Qingfeng is not stupid, he is not a smart and clever person, he listened to Jiang Han's method just now, and now he is still confused, how can he solve the problem on this paper in half an hour.

The eldest princess looked at Jiang Han, her expression was still calm, but there was some confusion in her eyes.

Qingfeng hurriedly waved his hand: "Jiang Gongzi, I, I can't do it." ”

Jiang Han said: "Miss Qingfeng, you can, believe in yourself." Your Royal Highness, if you don't believe it, do you dare to gamble? ”

Princess Ning Yue was curious and wanted to laugh in her heart.

This person is really bold and wants to bet with himself!

But she really wanted to know where Jiang Han's confidence in making a bet was.

Let Qingfeng learn arithmetic in half an hour and solve three difficult problems, how is this possible?

"What do you want to bet on?" The eldest princess said lightly, the implication of her words was that she was going to make a bet with Jiang Han.

Jiang Han groaned: "I haven't thought about what I want." ”

This guy was really funny, and he wanted to make a bet with someone, but he didn't think about what he wanted.

The eldest princess chuckled: "If you can let Qingfeng solve these three questions in half an hour, this palace will allow you a condition." ”

Jiang Han said: "The princess is atmospheric! If I can't let Miss Qingfeng solve these three questions in half an hour, the princess will have a life, and the grass people will obey. ”

After speaking, the eldest princess high-fived him and made a bet.

Hurriedly high-five, naturally I don't feel anything.

"Now, you can teach, do you need this palace to avoid it first?" The eldest princess said.

"No, Her Royal Highness the princess is listening." Jiang Han said.

Naturally, the princess can't be avoided, otherwise wouldn't it be suspected of cheating?

Jiang Han said: "Miss Qingfeng, I'll teach you a method called equation. ”

Qingfeng said blankly: "Equation? ”

Jiang Han picked it up and quickly wrote it on the paper, and at the same time, talked about the method of setting up unknown settings and listing equations.

It's just that he changed the unknown numbers X and Y to Tian Yuan and Di Yuan, making it easier for Qingfeng to understand.

He started with a one-dimensional equation, which even elementary school students can understand, but after learning it, he can solve many difficult problems.

Next, let's talk about binary linear equations, which are also known as binary linear equations.

Princess Ning Yue listened with a faint smile on her face at first, but the more she listened, the more she discovered this solution......

Not only magical, but simple!

It's too simple!

Hearing this, Ning Yue couldn't help but hold her breath, and her eyes flashed with brilliance.

Actually, you can still solve it like this?!

The solution is straightforward, fast, and easy to learn.

She looked at the three questions that Jiang Han had written on the paper again, and set up unknowns in her mind, listed equations, and quickly solved the answers.

How fast is this approach?

Even if Qingfeng hasn't solved the problem yet, the eldest princess knows that she is afraid that she is going to lose!

Qingfeng's comprehension is indeed inferior to Princess Ning Yue.

The eldest princess just listened and immediately learned this solution.

And Qingfeng, Jiang Han was stunned to speak three times before she understood.

Then, Jiang Han took the chickens and rabbits in the same cage problem as an example to solve the answer by setting up unknowns.

Then let Qingfeng solve the problem on the paper.

For the first question, Qingfeng only set an unknown number, solved the answer, and wrote on the paper: two hundred and fifty steps.

The second problem is more difficult, but it is still easy to solve the unknown numbers and the equations.

The third question is similar to the second.

In less than half an hour, Qingfeng wrote three answers on paper.

Jiang Han looked at Ning Yue and said, "Eldest Princess, believe my words now?" ”

Ning Yue was amazed in her heart, and said, "Are these solutions all what you think of?" ”

"Of course!"

Even if Jiang Han is thick-skinned, he feels a little hot when he says these two words.

Fortunately, Ning Yue didn't notice his subtle abnormality, and her heart was even more horrified.

This Jiang Han, if he doesn't come into contact, he really has a good talent.

As soon as I got in touch, I found that this talent was the world's greatest!

There have always been rumors outside that Jiang Han is a Wenqu star.

At first, the eldest princess scoffed.

Now it seems that this person is really a star in the sky!

"And these simple numbers, you also came up with them?" The eldest princess couldn't help but ask again.

She was referring to Arabic numerals written on paper.

This Jiang Han didn't admit it, because he wasn't sure if there was an Arab country in this world, although theoretically there was none.

Of course, the main thing is that he really can't honestly admit that he came up with this.

Jiang Han said: "No! These numbers belong to a small country in the Western Regions, and I found it easy to write, so I learned them. ”

The eldest princess said: "The number of countries in the Western Regions? Childe knows a lot! ”

Jiang Han said: "Your Royal Highness Princess, as long as you learn this method, can you solve it at what age a child?" ”

The eldest princess groaned slightly and said, "Yes! This method is so wonderful that if the mathematicians knew about it, they would have rejoiced. ”

Dayu also has mathematicians, but unfortunately it has declined.

Jiang Han said: "As for solving the wheat grain problem, another method is used. ”

Next, Jiang Han began to explain the summing of the equal ratio sequence.

Wait is more difficult than the number series, even Jiang Han knows nothing, so he can only pick what he knows.

Although Princess Ning Yue is smart, as soon as she comes into contact, she is like listening to a book from heaven.

As for Qingfeng, he didn't know what Jiang Han was talking about.

After Jiang Han's mouth was dry, Princess Ning Yue nodded as if she didn't understand.

"Is this the solution? No wonder Mr. was able to figure out the answer in such a short time. ”

Jiang Han smiled, thinking that his efforts were not in vain, and Ning Yue changed his title from son to sir, which shows the importance he attaches to himself in his heart.

"Thank you Mr. for your advice today, it's not too early, and the palace will leave first. If the gentleman has free time, he can come to the princess's mansion and treat each other in the palace. ”

Ning Yue got up and said softly.