Keywords: competition fun second grade primary school

This article is applicable to: the second grade of primary school.

Composition source:

This composition is about the second grade of primary school. The topic is: interesting mathematics-clever matchsticks. Everyone is welcome to contribute.

Interesting Mathematics-Clever Setting of Matchsticks

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One of my favorite books, Interesting Mathematics, is a prize book given to me by the school newspaper.

Continue to watch today, deeply attracted by it. I read an interesting question in the book: in the formula-+=-,it is required to move only one matchstick to make the answer become 130. Can you do it? As soon as I saw it, I became interested (another challenge to me) and got up at once.

I have done a lot of work on the matchstick, which should be easy to solve. So, I practiced:-=-,no; -+-=-,no; -=-,wrong; I thought as I spoke, and my head almost fainted. Forget it, let's have a rest first. So, I lay in bed, resting and thinking.

It suddenly occurred to me that to set the number 130, you need at least 10 matches, but there are only eight matchsticks in this formula, so it is impossible to set the number = 130 with matchsticks, so there is only another way. I suddenly realized.

I immediately jumped out of bed and continued to study this problem,++-,no; +-No; 4-Ha, that's right! I see, as long as you can express 130, how interesting mathematics is!

I'll show this question to my mother, too. My mother thought about it for a while, but it didn't work out. If so, then I am much smarter than my mother, hee hee ~

I really don't know, but I can't forget it at first sight. Wandering in the kingdom of mathematics is really mysterious!

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Mom's words: My son has always liked to read this "Interesting Mathematics". It is said that learning mathematics is boring, but the book Interesting Mathematics is infinitely interesting. Interesting Mathematics was written by Tan, a famous popular science writer in China. It is a rare good book with a wide range of topics and interesting contents. The book is divided into five parts, comparing mathematics to a big garden, a big workshop, a big supermarket, a big classroom and a big stage. It can be described as an entertaining and interesting book!

My son finished this problem and asked me. I was caught in a strange circle of thinking before, and I always thought it was an equation, and the result was predictable. I didn't work it out and failed. It's like a brain teaser, and it's comparable to a meditation old monk. When you are fully aware, you will be suddenly enlightened and have a bright future. I can't help but admire my son's cleverness, son, you are really great!