Chapter 1790: The victory of mathematics (1/2)

The white-haired old Taoist Zhen Yang showed joy when he heard the words, and said: ”Great! Xia Jushi is really happy! There are several problems that have plagued the poor Tao, the first problem is...”

Speaking of this, the old true Yang shook his head and said, ”Today, there are pheasant rabbits in the same cage. There are thirty-five heads on the top and ninety-four legs on the bottom. What are the pheasant rabbits?

After hearing it, Xia Ruofei suddenly showed a strange look, she couldn't tell! This true Yang Dao with thick eyebrows and big eyes is still a math lover! Even if his question is written up, it will not change the nature of a math problem! Isn't this the problem of the original chicken and rabbit cage?

Those few words of Zhenyang Old Tao, translated into modern words: There are chickens and rabbits in the same cage, there are 35 heads on the top, and 94 feet on the bottom. Ask how many chickens and rabbits each have. only?

Perhaps this was a very clever mathematical problem in ancient times, but in this era, a junior high school student can easily solve it, and it can be solved by formulating a linear equation in two unknowns. This is also called a problem?

After Zhen Yang finished talking about this question, with a smile on his face, he said: ”Ju Shi Xia, you can have a stick of incense to answer this question.”

As soon as his words fell, Xiao Dao Tong Qingfeng had already brought in an incense burner that had already been prepared, and a newly lit incense was inserted in the incense burner.

Xia Ruofei couldn't laugh or cry, and said directly: ”Zhenyang Daochang, don't have to be so troublesome, I have solved this question.”

The old true Yang raised his eyebrows and said, ”The layman is so fast? Then tell me, what is the answer?”

Xia Ruofei smiled slightly and said, ”23 chickens and 12 rabbits, right?”

True Yang Lao Dao naturally couldn't really be trapped by the problem. The question he asked Xia Ruofei was actually a test.

Xia Ruofei believed that if other expedition members including Ling Qingxue would also enter this scene, the old true Yang Dao would also use the same tone and tone to throw the problem to them.

As soon as Xia Ruofei said this answer, Old Zhen Yang couldn't help raising his eyebrows, and said, ”This is indeed the answer to this question...”

”So, I have solved this problem?” Xia Ruofei asked with a smile.

”Wait!” Zhen Yang said, ”I want to know what method Xia Jushi used to calculate in such a short time?”

Xia Ruofei said in his heart: ”A linear equation in two unknowns! Isn't it just a direct calculation?”

But Zhenyang Lao Dao definitely doesn’t understand binary linear equations. When Xia Ruofei was considering how to change the solution to an easy-to-understand method, he suddenly thought of an interesting problem-solving method he had seen on the Internet before. It seems ridiculous, but it can be calculated quickly.

So Xia Ruofei smiled and said: ”My method is very simple! Daoist, with 35 heads, it means that there are 35 chickens and rabbits in total, right?”

Old Zhenyang nodded, and did not speak, because it was basically nonsense.

Xia Ruofei smiled and continued: ”Let the chicken and the rabbit raise both feet, then there should be 70 feet missing, right? Of the 94 feet, there are 24 feet left. Because the chicken has only two feet, after they are lifted up, the remaining 24 feet on the ground are all rabbits. And each rabbit has raised two feet, so they all stand on two feet Twenty-four feet naturally correspond to twelve rabbits. There are thirty-five chickens and rabbits. If the number of rabbits is twelve, the chicken will naturally be twenty-three. Doesn’t the answer come out?”

Old Zhenyang was dumbfounded, he didn't expect the answer to be so simple.

After a while, he said with a weird look: ”How can this chicken and rabbit lift their feet obediently? Also, when the chickens both feet are lifted, what kind of posture is this...”

Xia Ruofei almost burst out laughing, he squeezed a smile and said: ”Dao Master, this is not important, it is just an assumption! The point is that this method can get the answer the fastest, right?”

The old true yang thought for a while, and said: ”Xia Jushi is very talented! This problem-solving method is very ingenious, and the poor Dao admire it!”

”So, this question is solved next?” Xia Ruofei asked with a smile.

”Of course!” said the old true Yang Dao, ”the poor Dao still has a problem here, and I hope that Lay Xia will give him any advice.”

”Say Chief, please!”

The old true Yang pondered for a moment, and then he said: ”There are things that don't know the number, two out of three or three, three out of five or five, and two out of seven or seven. How about things?”

Got it! It is another classic ancient math problem, and it also comes from it.

This question is translated into modern words: there is a pile of things, three and three numbers will eventually be left two, five and five numbers will finally be left three, and seven seven numbers will finally be left two. Find this pile of items quantity.

There was always a faint smile on Xia Ruofei's face. There was a trap in this question. The trap was: The answer to this question is not unique. To be precise, it should be an arithmetic sequence with a difference of 3*5*7. If the ancients who have not learned much mathematics face this question, they can get the answer in a number test, but they may have overlooked this question. There are many answers. If only one is mentioned, it is probably not counted. correct.

After Zhen Yang finished asking the question, he looked at Xia Ruofei with a smile.

And Xia Ruofei also had a relaxed look, and after a little thought, he said: ”Dao Master, the answer to this question is not the only one. There should be at least 23 items in this pile, then 128, and then maybe 233. One, and so on, add 105 to each answer to get a new answer, so there are countless answers.”

Xia Ruofei's answer is expressed in mathematics, that is, n is an integer greater than or equal to 1.

Xia Ruofei's answer is very rigorous, it can be said that it is not leaking, even if the old way of True Yang is looking for flaws, it is impossible to find.

Therefore, he just pondered for a moment, then nodded and said, ”Senior wise man! This question has been solved!”

This time, Zhenyang Old Dao didn't even have any interest in asking Xia Ruofei to talk about the calculation method, and directly judged that Xia Ruofei had successfully solved the problem.

Soon, Zhenyang Lao Dao went on to say: ”There is one last question, I hope Jushi Xia can also help Lao Dao!”

Xia Ruofei secretly breathed a sigh of relief. He was afraid that this basic math problem would never end. Although it was not difficult for him, it was a waste of time.

Moreover, the test of the first floor of the tower, the test of mathematics, is really unexpected.

Fortunately, the power of setting these levels is not too horrible and interesting, only three questions are arranged in total.

Therefore, Xia Ruofei has only one idea at this time, and that is to end it quickly!

He listened to the words of the old true Yang Dao, and said quickly: ”Dao Master, please say!”

The old true Yang said with a serious face: ”The last question is quite difficult, but I still can only give Jushi Xia a stick of incense. I hope Jushi Xia can make persistent efforts to solve all the problems in one go!” Weichang