"What is the Ninety-Nine Table?" Tao Liuyi looked at Yao Changsheng and asked curiously, "This abacus also has a formula." ”

"This ninety-nine table is conducive to your learning arithmetic." Yao Changsheng looked at them and smiled slightly, and said unhurriedly, "Ninety-nine-eighty-one...... Two-two-two-four! ”

The more Tao Qini listened, the more familiar she became, isn't this the ninety-nine multiplication table!

It's just that its order is the opposite of the mantra of later generations, and one is missing......

It turns out that there was a ninety-nine multiplication table so early.

"How do you use this?" Tao Liuyi scratched his head and said with a distressed expression.

"This one will be used often, you memorize it first." Yao Changsheng looked at them and said, "How to use it, I'll teach you slowly." ”

"Sleepy or not, let's talk about it tomorrow! Anyway, you can carry it on the road. Yao Changsheng looked at them and said.

"Not sleepy, not sleepy." When Tao fifteen heard this, he immediately said, "It's important to memorize this." ”

"Anyway, Ming'er won't leave, and she can sleep during the day." Tao Liuyi looked at him and said with a smile.

"Okay, let's memorize the nine first." Yao Changsheng looked at them who were eager and said with a smile, "If I say a word, you will say a word." ”

Yao Changsheng said a word, and the three members of the Tao family followed suit.

Tao Qi Nike didn't want to waste time on this, so she took a knife and wood and continued to make calculations.

Yao Changsheng stopped, and he didn't dare to make a sound, for fear that his cold opening would scare her, and the slightest deviation of the knife would cause blood to be splashed on the spot.

The three members of the Tao family stared at Yao Changsheng directly, waited for a long time and didn't see him speak, and looked at him along his line of sight, why didn't this kid know the severity!

As soon as Tao Fifteen was about to speak, he was covered by Shen's mouth! Glaring at him, tilting his head, he whispered in his ear, "Don't scare Niel. The words fell, and he let go of his hand.

The four of them patiently waited for Tao Qini to make an abacus bead and stopped the knife.

Tao Qini made an abacus bead in the blink of an eye, raised her eyes to look at them who were looking at her, and said, "Hey? Why don't you carry it! ”

"What else are you carrying?" Shen pressed the black knife placed on the straw mat and said, "What about you! Why don't you follow the back. ”

"I'm ......," Tao Qini hesitated for a moment, "I'm not in a hurry, I'll make a plan first." ”

"I have an abacus, I'll do it when I come back, and it's more important to memorize this now." Tao fifteen looked at her with a straight face and said solemnly.

"Alright! All right! Tao Qini rolled her eyes elegantly and said helplessly, "I have a question?" His eyes looked at Yao Changsheng.

"Say!" Yao Changsheng looked at her and said very simply.

"We counted from small to large, from the beginning." Tao Qini blinked her innocent eyes and looked at him and said, "Also, also, why is there no more to two, one!" ”

"This ......" Yao Changsheng thought for a while and looked at her and said, "The "Guanzi" between the Spring and Autumn Period and the Warring States Period, the book mentions: An opera is the number of ninety-nine to respond to the way of heaven. As for why there is no one, because in this ninety-nine table, one and any number together are any number. He smiled slightly, "As for the order you said, it was in the Song Dynasty." It's just that I'm starting from nine, and if you want us to do it, we can start from the beginning. He smiled and said, "We often compare our minds to little ninety-nine." ”

"It turns out that this little Jiujiu is from here." Tao 15 suddenly realized.

"Yes! This mantra is often called the Ninety-Nine Song and the Ninety-Nine Table, and it is a must-remember for children during enlightenment. Yao Changsheng looked at them and said with a smile.

"It's been there so early." Tao Liuyi said in surprise.

"yes!" Yao Changsheng nodded with a smile and said, "It was already very common during the reign of Duke Qi Huan, and by the time Qin Shi Huang unified the Six Kingdoms, this Ninety-Nine Table was already an arithmetic textbook at that time. He said with high interest, "The Spring and Autumn Period and the Warring States Period not only invented the ninety-nine table, but also invented the decimal system. The two of them are used together, making arithmetic easier, more convenient, and faster. Kids do! ”

Tao Qini nodded in her heart when she heard this, this great invention has given almost all Chinese people excellent basic computing capabilities, and it has given Chinese people an innate advantage in the world now and in the future.

Yao Changsheng suddenly laughed, "Hehe......"

"Mr. Yao, what are you laughing at?" Tao fifteen looked at him who was laughing inexplicably and said.

"I have seen books on arithmetic in the Hanlin Academy, they do not have a carry system, and in principle they need to be infinite, so it is impossible to have a ninety-nine table." Yao Changsheng's eyes were beating with a bright light, looking at them and saying with a smile.

"And what do they do?" Tao Liuyi looked at him and asked curiously.

"This one! Stacked repeatedly, it is very cumbersome and complicated. It's not as simple as ours! Yao Changsheng's bright eyes looked at them and said with a smile, "Our ninety-nine watches are simple and easy to memorize, and they are also easy to use." ”

"Since Niel asks for one, let's start from the beginning." Yao Changsheng looked at her with warm eyes and said in a soft tone.

Yao Changsheng said a word, and they followed it to learn a sentence, and they would soon memorize it.

Tao Qini couldn't read a sentence without exception, but her hand was not idle, and she continued to carve abacus beads.

Yao Changsheng couldn't help but speak, "Tao Qini, it's not good for you to use two things!" ”

Tao Qini pursed her lips when she heard this, she wanted to refute it, but after thinking about it, she thought about it and said, "I know, I won't do anything else, okay?" ”

Yao Changsheng raised his eyebrows and looked at her in surprise, he had prepared a stomach full of big truths, and he didn't use it at all.

"So why are you surprised? I have a bad attitude. Tao Qini raised her eyebrows and looked at him and said meaningfully.

It's just that the attitude is so good, so good that Yao Changsheng is suspicious.

"Don't worry, there's no pit ahead! So what to do carefully? Tao Qini looked at him with smart eyes and said funny.

was scared of being stimulated, and suddenly his attitude changed, especially the suspicious Yao Changsheng, can he not doubt it!

"I never tell lies." Tao Qini's clear eyes looked at him and said seriously, "I'm going to know how to memorize, don't I have to memorize it." ”

"Of course." Yao Changsheng's dark eyes shook slightly when he heard this, I see, new questions came to mind, this is obviously enough, how can you still follow the study honestly!

Turning his gaze to the three members of the Tao family, it won't be because of them!

The sword eyebrows raised slightly, and his gaze twirled between them.

"What's wrong with Mr. Yao? Watch us do something? Is there something wrong? Tao Liuyi looked at him with a puzzled face and said.

"Nothing?" Yao Changsheng looked at them and shook his head slightly, and then said, "Now I will teach you the simple ones first, if you want to learn arithmetic well, wait until you go to the city to buy a copy of "Nine Chapters of Arithmetic", it is very rich in content, and summarizes the mathematical achievements of the Warring States, Qin, and Han dynasties, so it is more convenient for you to learn." ”

"Good!" Tao 15 responded happily.

Being able to be an official stimulates the Tao family very much, and they are very active in learning.

Yao Changsheng saw that they were so obsessed with being officials, and thought to himself: There is a difference between this official and an official, let's learn it first!