Lao Lin shuttled between the cafeteria hall and the back kitchen.
After a while, he came over with a cloth bag, threw it on the table, and made a loud noise.
The porridge was finished, and they all stared at the cloth bag, and looked at Lao Lin curiously.
Lao Lin: "Stretch out your hand."
The small palms spread out.
Lao Lin opened the cloth bag, without any explanation, took out a handful of things from it, and put it in their palms.
The yellow particles are round and round, they are actually soybeans.
"Count and see." After finishing speaking, Lao Lin continued to work.
The four of them were holding handfuls of soybeans and looked at each other in blank dismay.
But since the master said to count, let's count, so Pei Zhi took the lead in counting.
The first number was small, and soon, each of them ran out of counts.
Lao Lin also just finished wiping the table, came back with a rag in his hand, and asked, "What do you gain?"
"I have 12 soybeans!" Lu Zhihao said.
"I'm 9!" This is Hanamaki.
Lin Zhaoxi was very happy: "I am more than you, I am 13!"
Pei Zhi didn't speak, he lined up the soybeans and looked up at Lao Lin.
Lao Lin didn't speak, and continued to give each person a handful of soybeans, then turned to wipe the table and go to work.
"What's the gain?" Lao Lin would ask this question every time he turned around, but they didn't have any serious answers.
Lu Zhihao carefully arranged the soybeans issued by Lao Lin in the order of 1 in the first row and 2 in the second row.
Pei Zhi rounded up the soybeans given by Lao Lin, 10 in a row, and in groups of 10.
Hanamaki, after ordering the Hanamaki, just throw the soybeans into the empty porridge bowl as you like.
A bag of soybeans is finally empty.
Lao Lin finally finished his work and sat back: "Have you finished counting the soybeans?"
Nodding like pounding garlic.
"Now, suppose none of you know how to add, but I want you to tell me right away, how many soybeans do you each have?"
Lin Zhaoxi bowed her head, and was just about to subconsciously count the sum of soybeans each time, when she heard what Lao Lin said.
So she hurried to order how many rows of soybeans she had. She is 10 soybeans arranged in a row, a total of 11 rows, zero 3, so it is 113.
"125." Pei Zhi had finished reporting the answer.
Lin Zhaoxi went to see Pei Zhi, and Pei Zhi had already arranged a square array of 10 horizontally and 10 vertically, with a total of 100 soybeans, and the remaining 2 rows and 5 soybeans
Lu Zhihao stared at his soybean triangle for a long time. He couldn't help it, so he began to count 1, 2, 3, 4, 5 honestly.
Hanamaki rested her chin on one hand, staring blankly at the pile of soybeans he threw into the porridge bowl.
"Congratulations, you have replayed the process of the earliest birth of mathematics." Lao Lin smiled, "Do you want to applaud yourself?"
Lao Lin's joke was very cold, each of them looked at their soybean array, too cold to speak.
It wasn't until Hanamaki hiccupped that everyone woke up.
Lao Lin asked, "Is there any question?"
"Ah?" Lu Zhihao looked up, "What did you just say?"
"I said that the process of the birth of the earliest mathematics is very great and ingenious. Please cooperate and applaud yourself?"
Including Pei Zhi, each of them continued to be sluggish.
"Come on, let's imagine that at the beginning of the development of human society, when everyone was still wearing small tiger skin skirts and dancing around the fire, of course there was no addition, subtraction, multiplication and division at that time, and even 123456789...these numbers No." Lao Lin patted his chest like a savage, causing the children to giggle.
"Every day, primitive humans have to go out to hunt, otherwise they can't survive. At the beginning, everyone hunted casually, no matter how many small animals they hunted every day, but one day, Hanamaki found that it was not possible, and he said I had to remember , How many prey do I have every day, otherwise Lu Zhihao next door would come to my house to steal food?"
"So, he started to carve letters on the wall. Each 丨 represents how many prey he killed today."
As Lao Lin said, he put a soybean in front of Hanamaki, comparing the movements of Keji, and imitated Hanamaki's voice dubbing: "Today, there are so many chickens."
He put down a few more ducks, representing a few more 丨: "Tomorrow, there are so many ducks."
After repeating this several times, there are countless soybeans in front of Hanamaki.
"Ah, here comes the problem! Suddenly one day, Hanamaki wanted to know how many prey he had killed. When he came home, he saw the entire wall of 丨丨丨丨丨... collapsed."
As Lao Lin said, he shook the entire bowl of soybeans in Hanamaki, making them rustle in the bowl, which symbolized the disorderly counting method of the wild man Xiao Hanamaki's entire wall.
"Uncle, you are so childish!" Hanamaki protested.
Of course it is childish, Lin Zhaoxi thought, this is a story I heard when I was five years old.
Lao Lin put down the bowl, and suddenly became serious again: "The problem of flower rolls is not only a problem of flower rolls, but also occurs in the homes of many people in the tribe. Primitive humans always face various problems involving counting in daily production and life. As happy as you are now, they don't even have ready-made numbers to use." Lao Lin touched Lu Zhihao's head, "So, in order to solve many problems of 'countless' and 'inaccurate' in production and life, they started to create. "
Lao Lin's hand moved to the triangle of soybeans in front of Lu Zhihao, and his fingers clicked on each row of soybeans in turn, with a very solemn tone: "The process of generating numbers is roughly like this." Lao Lin said, "If you are lucky enough to see the ancient Babylonian Clay tablets, you will find that he used a pen with a triangular section to carve, which we now call cuneiform. People at that time used one notch to represent our current number '1', and two notches to represent Representing our current number '2' and so on, but by the time '10' they had a new counting symbol."
Lao Lin drew a "