"Little... Sister Xiaozhi, are you okay? Hongling asked with some concern.

Wasn't it good just now, how to draw a few lines and not move, staring wide-eyed, open-mouthed, and surprised, Miss didn't fall into evil, right?

Zheng Yanzhi came back to her senses, shook her head, and said while looking at the numbers on the paper: "It's okay, just think about something that is clearly calculated, Hongling, you step back, don't tell you not to speak." ”

Hongling flattened her mouth and whispered, "Got it, Sister Xiaozhi." ”

Miss is like this, usually good, but once she learns to calculate, she will change as if she is a person, and she just blamed herself for disturbing her study.

Zheng Yanzhi thought for a while, and said to Lu Ting with a respectful face: "Lu Gongzi is really talented, such ingenious problem-solving skills can also be thought of, the slave family admires, the slave family sees a little mystery in this question, and there are still some things that I don't understand, and I ask Lu Gongzi to solve the puzzle." ”

As soon as the connoisseur made a move, he knew if there was one, although it was not from one to ten thousand, but the reason was the same, Lu Ting only wrote one to one hundred, also to facilitate his own understanding, Zheng Yanzhi put away her suspicions, and her attitude was correct.

Even if he is unhappy, Lu Ting also has real talent and learning, and for those who have real talent and learning, it is normal to lower his stature a little.

This question is very convenient to calculate using the principle of equal difference, Lu Ting explained it briefly, and then listed the formula, that is, the first number and the last number are added, and then multiplied by the quotient of the last number divided by two, and the answer will come out.

Lu Ting explained while columnist: "Miss Xiaozhi is optimistic, this is the calculation method from one to hundred, and from one to ten thousand is also calculated by this method, one thing should be noted, there must be a regular number to calculate in this way, for example, like one, eight, eleven, twenty-three these numbers without scale, this kind of skill is not used, and you have to calculate honestly." ”

"Understood" Zheng Yanzhi nodded again and again: "There are rules that can be applied, and those that are irregular can only be counted one by one, which is a pity, such a good method cannot be universal." ”

Zheng Yanzhi was really convinced now, to be honest, I felt that Lu Ting was talking about it at the beginning, but I didn't expect Lu Ting to turn it into reality again, according to his calculation method, the addition from one to ten thousand can really be calculated with a few breaths, not to mention adding to ten thousand, it is not difficult to add to ten thousand, that is, one hundred thousand, one million, ten million, ten thousand, such a simple law, why didn't I find it?

I really want to see what the brain of this prodigal son is like, so many wonderful ideas.

"No one is perfect, and there is no omnipotent problem-solving skill." Lu Ting said with a smile.

Complete the task, call it a day, and now I can't clean up Wu Lin and that bullshit bearded boy, but I still have a lot of confidence in dealing with a little girl.

Zheng Yanzhi thought about it, and suddenly frowned and said, "Lu Gongzi's method is indeed wonderful, but it also has shortcomings. ”

"Deficiencies? Miss Shiba has any doubts, just ask them. Lu Ting said generously.

This little pretty girl is not crossing the river and demolishing the bridge, deliberately picking thorns, just turn her face when she learns the skills.

Zheng Yanzhi didn't notice Lu Ting's expression, but picked up the pen, added one hundred and one after one hundred, put down the pen and said with some doubts: "Lu Gongzi, when you encounter this kind of situation with a remainder, in addition to double, that is, from one to one to one, find out and add one hundred and one later, is there still a way to directly use Gongzi's column to complete?" ”

"The remainder? Hasn't Miss Shiba learned decimals? ”

"Decimals?" Zheng Yanzhi paused for a moment, and said with some hesitation: "Is the decimal number that Gongzi said zhang, ruler, inch, centimeter, millimeter, second or micro?" ”

Lu Ting patted his head and said with a wry smile: "It's me who is confused, the decimal is a stranger to Miss Xiaozhi, and it is normal not to understand." ”

In ancient times, there was no concept of decimals, and there were fractions in the nine chapters of arithmetic, and the first to express this concept in words was Liu Hui in the Wei and Jin dynasties. In the process of calculating pi, he used 7 units, such as ruler, inch, minute, centimeter, millimeter, second, and sudden; For the smaller units below the sudden, they are no longer named, but collectively referred to as "micro", what Xiao Qiaowen said, that is, the "decimals" adopted by Liu Hui in the Wei and Jin dynasties, the real decimal appeared and standardized, and it took hundreds of years later.

Zheng Yanzhi's eyes lit up, and she immediately went to the side of the coffee table and poured a cup of tea, and gently placed it in front of Lu Ting: "Master Lu, your mouth is dry, please use tea, decimal is strange to the slave family, and with Lu Gongzi teaching, it is not a stranger." ”

Decimal fraction? New tricks? After Lu Ting simplified the numbers last time, Zheng Yanzhi used it more and more, and now when she heard Lu Ting say that she had never heard of "decimals", she came to her senses on the spot.

Not only came to the spirit, but also came to things, and took the initiative to pour tea for Lu Ting.

A few people who were looking at the garden from a distance saw it, and they were all dumbfounded, what was going on? Miss Zheng brought Lu Ting to the back garden, which was already surprising, and now... Pour him tea yourself? Oh my God, the eldest lady of the Zheng family in Xingyang, poured tea for a well-known and even somewhat bad reputation in Suzhou?

Are you dazzled? One of the maidservants wiped her eyes, for fear that what she had just seen was a hallucination.

Fu Zhi raised his head slightly, his eyes were full of pride, the son is the son, Miss Xiaozhi is the confidant of Mrs. Lin, isn't she quite temperamental just now, her eyes are almost looking at the sky, how much effort is to be obedient, you have to pour tea.

Hongling on the side covered her face with one hand helplessly, not knowing what to say.

The young lady is too reserved, she can't say anything, and she breaks her word and gets fat in the blink of an eye; Before he came, he said that he wanted to show Lu Gongzi the color, and when he had a good taste of begging, he took the initiative to keep people; threatened to let Lu Gongzi clean up the silt in the lotus pond and take a good breath, and now he has become a maid ring who pours water.

It's the opposite of what I imagined.

Yo, the little girl has a strong desire for knowledge, and took the initiative to pour the tea, Lu Ting was happy in her heart, took the teacup unceremoniously, and said casually: "It's a pity that I didn't taste the osmanthus cake made by Miss Xiaozhi herself, and I didn't have a good taste." ”

A pair of pink fists were clenched in his sleeves, this prodigal son of Dengtu not only knows how to pick and choose, but also knows how to make inches, and he is a little unhappy, but he didn't show it at all, and said with a smile: "It's too late to do it today, do it tomorrow, and send someone to the prince's mansion." ”

Hongling covered her face with her hands and was speechless.

Lu Ting nodded with satisfaction, wrote the word "1" on the paper, and began to explain: "The decimal is actually very simple, that is, the smallest value is more into smaller parts, the principle is similar to the principle that the hour is divided into a quarter of an hour, a pillar of incense, and a cup of tea, but the decimal is more stable..."

So Lu Ting explained the principle of decimal from shallow to deep, and under Zheng Yanzhi's repeated requests, he used the method of decimal to solve the calculation of singular numbers in the equal difference formula, which involves the multiplication and division of decimal points.

After talking for so long, his mouth was dry, Lu Ting picked up the teacup and drank the tea that had been cold in one gulp, and then he breathed a sigh of relief: "Miss Xiaozhi, there is no problem now." ”

As he spoke, Lu Ting put the empty teacup a little forward.

The meaning is obvious, the teacups are empty, let's add tea.

Zheng Yanzhi, who was still very clever and knowledgeable just now, didn't seem to see the empty cup, and said with a smile: "Lu Gongzi is really talented, the slave family admires, if it is time, I really want to learn more from Lu Gongzi, but it is a pity that the owner has left a big mess to do, delaying Lu Gongzi for so long, it is really bad, and I dare not keep Lu Gongzi, Hongling, send Lu Gongzi out, by the way, let people prepare the car, the road is so far, it is too tiring to walk." ”

Hongling responded, walked up to Lu Ting with a smile and made a gesture of please: "Master Lu, please come here." ”

This is... Rushing customers?

Lu Ting was stunned, this little pretty maid, she changed her face too quickly, she was still respectful just now, and she was about to take the gift of a disciple, and as soon as she finished explaining to her, she drank half a cup of cold tea, and even saved the ring of serving tea to the guest, and directly opened her mouth to send herself out?

It is said to be a send, but in fact, it is to rush.

The front solution of the equal difference formula is considered a transaction, and the back explanation of the decimal is considered a white prostitute (piao), Lu Ting was a little indignant, this little pretty maid had been trying to take the initiative just now, but the seven inches let herself be pinched, so she could only put down the shelf, but she didn't expect that as soon as she achieved her goal, she would immediately cross the river and tear down the bridge, needless to say, there must have been a lot of resentment in her heart.

If it was a weekday, he would have left, but Lu Ting couldn't leave at this time, there was no problem with passing, but the travel expenses had not been solved yet.