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Elementary School Mathematics Story: Naughty Number "3"
The naughty one in the natural number family is 3. Because he is short, everyone affectionately calls him "Little Three".

Xiaosan never walks easily. When he walks, he jumps and jumps. When he is hungry, he goes forward and looks back.

At this time, Xiao 3 cocked his head and ran forward. "bang!" He bumped into an old man with a white beard.

Grandpa with white beard is here; "Xiao San, you are running around again. It's not good to hit a car and touch a lot of people. "

Xiaosan disapprovingly said, "It's okay to bump into it. There are so many running around! " "

"Are you okay? From now on, you will meet another person, and that alien will breed with another person. If you don't believe it, you will bump into it. " Grandpa with white beard pointed to mistress, and the difference disappeared.

"Who play who do multiplication? Hey, this is interesting. I'm going to hit it and have a try. " Xiao San said and ran forward.

Far away, I saw Count No.2 sitting on a stone, and Xiaosan bowed his head and bumped into Count No.2.. Just listen to the sound of "dong", and a white smoke rises on the ground. After the white smoke, the number 2 is gone, and the little 3 is gone, but the number 6 is on the stone. What about Xiao San? It turns out that the small 3 and the number 2 are tightly tied together by a multiplication symbol "×", which becomes the belly of the number 6, and 2×3=6.

Count No.6 stood up, patted the dirt on his trousers and walked to Even Village. When Xiao San saw that he was going to even village on the count of six, he was anxious. He shouted, "No, the direction is wrong. I don't live in a flat village. I'm a freak. I live in a strange village. "

No.2 said. What are you yelling about? Who told you to hit me and multiply me? Any odd number will become an even number if you multiply it by my number 2. "

Xiaosan said in surprise, "Are you that powerful? What if the even number is multiplied by you? "

"Even the second time with me, of course, forget it. In short, any natural number multiplied by me will become an even number. "

Small three begged: "count to two to help, you are even and I am odd." It doesn't matter to us. Let's work together to get rid of this multiplication sign. "

Count Two shook his head and said, "No! Who says we're okay? Think about it, what is your little 3 except odd number? "

Xiaosan thought for a moment and said, "I am still a prime number except odd." Do you know what a prime number is? A prime number is a natural number that can be divisible by other natural numbers except 1 and itself. Except 1, 1 is not a prime number. "Count to two?" I'm a prime number, too. I'm family with you. "

"liar! I have many friends with prime numbers, such as 5,7, 1 1, and so on. If you count 2 as an even number, how can it be a prime number? "

"Whether it is a prime number is measured by the definition of prime number. My number 2 can be divisible by other natural numbers except 2 and 1. Prime numbers, of course. "

Xiaosan thought for a moment and said, "Yes! You meet the definition of prime numbers, and you are prime numbers. "

"I am an even number of prime numbers and the smallest prime number."

"Yes!"

"I am still the smallest even number in the family of natural numbers."

"liar! The smallest even number is zero. "

"Zero is smaller than me, but zero is not a member of our country's natural number family!"

Small three suddenly enlighted, nodded and said; "yes! Zero is not a natural number, and natural numbers start from 1. "

"One, two, three!" Xiao San waved to No.2 and said; "Goodbye, the smallest prime number and the smallest even number in the family of natural numbers."

Xiaosan started to run again. He tried to count as he ran, but he missed! Even numbers become even numbers, but you can't go back to odd villages.

Little 3 was only thinking about things and accidentally bumped into the ground with the number 5. After a puff of white smoke, 3×5 becomes 15.

Xiaosan said happily, "It's okay to play odd numbers. Three, five, one, fifteen, the result is still odd, and it has not changed at all. "

Count No.5 muttered, "Nothing has changed! You count 3 as a work, and I count 5 as a prime number. When we multiply, it becomes 15, and 15 is not prime. "

Xiaosan touched the back of his head and said, "Yes! Multiply by a prime number that is not 2. Although the product is still odd, it is no longer prime. Alas! Seriously, what number did we become after multiplication? "

The number 5 means, "We multiply by 15. This 15 can be divisible not only by 1 and this god, but also by you -3 and me -5. This natural number is called a composite number. "

"If it becomes a composite number, then I will quit." Xiaosan struggled to break away from the multiplication sign and ran with his head down. 1 of "dong", and hit a number.

After spraying a mouthful of white smoke, Xiaosan shook her head and found that she had not changed. He still counts to three. Strange! I clearly dialed a number, why hasn't it changed? Is it a dream?

I only heard many people say in their bellies, "You hit me."

"Who are you?"

"I am 1!"

"Oh, I remember." Xiao 3 said, "Multiply any natural number by 1 to get the original number. 1 This number is really strange. "

Small 3 company jumped up and ran forward, and it was about to hit a number in front of the station. Suddenly, a man pulled him: "You can't hit him, it's dangerous!" " "

When Xiaosan saw it, it was pulled by Grandpa White Beard. Xiao San said unconvinced: "How can I miss?" I played even and odd numbers. What's so great about him? I'm determined to hit it. "Then he lowered his head and rushed forward.

Grandpa with white beard said, "Look who he is. When the count in front turned around, Xiaosan got a fright. It turned out that he counted 0.

Grandpa with white beard said, "Multiply 0 with any number to get 0. Rush into 0, multiply it with 0, and it will become 0 forever, and you will never see your little 3 again. "

Hearing this, Xiao 3 broke out in a cold sweat. He quickly bowed to Grandpa White Beard and said, "Thank you for saving my life. I will never run around again. Grandpa, who are you? "

"Bye bye, let you he has a lot of knowledge, have a deeper understanding of the multiplication of natural numbers. However, you must study hard to make continuous progress. You want to ask who I am? Come and see. " After a burst of white smoke, a big math book appeared. Ah! Grandpa White Beard turned out to be a math book.