Prior to this, Tang Li had also taught Ning Yuchu arithmetic, but it was only a simple ninety-nine multiplication table, as well as addition and subtraction.

Let him have the concept of arithmetic, which can be regarded as an introductory teaching.

But compared with "Nine Chapters of Arithmetic", it is the difference between bronze and king.

Although the state has arithmetic subjects, it is not in the names of scientific examinations at all levels, and it can be said that arithmetic has become a dispensable subject.

Most of the readers only know ancient poetry, poetry and songs, and the common people only need to know simple algorithms, and arithmetic is even less important.

However, those in power must understand this subject, and only in this way can they reasonably implement policies and better solve people's livelihood problems.

For example, building bridges, digging canals, discharging floods, paying taxes, procurement, etc., all aspects require complex calculations.

And "Nine Chapters of Arithmetic" basically covers these issues, even if they are not involved, they can be bypassed and draw inferences.

Tang Zhuoyu has been interested in arithmetic since he was a child, and after entering the National Prison, he devoted himself to research, and he was quite accomplished in this area.

A teacher once predicted that with his ability, there would be no problem in joining the Ministry of Industry to worship Shangshu.

It's just that he is young, and he still needs to learn more and sharpen more.

Tang Zhuoyu took over Ning Yuchu's arithmetic class, although he was selfish, but he was a serious and rigorous person, and he would not teach perfunctory because of this.

With one hand to protect the jade cabbage, and the other hand to transform the silk, he has to grasp it with both hands.

And this is the obscure "Nine Chapters of Arithmetic" in the eyes of readers, and for him, it is only an entry level.

Therefore, he chose this well-informed book as the teaching content.

When he taught, he didn't think about whether it would have a profound impact on Ning Yuchu.

It can only be said that the willows are unintentionally inserted into the willows.

"Today, we will learn 'Fang Tian' first, as long as the son of the world can understand the first three questions today, we will leave the class."

Ning Yuchu listened to it for a long time, and only understood this sentence did he understand.

He nodded like pounded garlic: "Okay, okay, hurry up, the master has decided to go ice fishing after class." ”

Tang Zhuoyu smiled lightly: "Then please turn the first page and the first question." ”

"Today, there are fifteen steps in the field of wide, from the sixteenth step, ask for the geometry of the field?"

Ning Yuchu frowned at this line of words.

He knew all these words, but when they were put together, he couldn't read them.

Tang Zhuoyu walked to the blackboard, picked up the chalk and drew a rectangle on it, marked with numbers.

The whip pointed to the line and said: "Wide here is wide, from that is, long, let's take this problem as an example to learn the area calculation method of plane figures." ”

"The formula for calculating a rectangle is to multiply the length by the width, so does the prince know how to do this?"

Ning Yuchu: ......

"Fifteen times sixteen equals, equals...... Five-six-three-five-six-thirty......"

He had only learned multiplication of single digits, and he had not yet had time to learn multiplication of two digits.

Tang Zhuoyu saw that he couldn't answer it after reading for a long time, so he changed the question.

"Excuse me, Shizi, can you know the conversion of length units?"

Ning Yuchu: ???

Tang Zhuoyu saw that he was full of question marks, and knew that he did not have a solid foundation.

He sighed: "The prince close the book, let's start with the length conversion." ”

Ning Yuchu: ...... It seems to be despised.

Tang Zhuoyu wrote on the blackboard as he spoke: "There is a record of length conversion in the "Sun Tzu Sutra", one zhang is equal to ten feet, one foot is equal to ten inches, one step is equal to six feet, and one mile is ......."

He knew that Ning Yuchu would never forget it, and after he finished talking about it, he began to teach multiplication and division of more than two digits.

Tang Zhuoyu is a person who pays attention to efficiency, he doesn't have any nonsense, every word is the essence.

After Ning Yuchu's entire class, his brain couldn't keep up with his speed.

[On the last day of PK, it depends on whether you can advance or not! ] Rush the duck! See you at 12 noon on the next shift! 】