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According to the book classification of Xinhua Bookstore, understand the classification of society
Classics and Philosophy
Social science, political law
Military science and financial management
Historical geography and cultural education
Culture and education in primary school and culture and education in junior high school
High school culture and education, language and writing
Chinese literature and foreign literature
Music and art sculpture
Photography, film, television and dance drama
Calligraphy and seal cutting · Natural Science
Mathematical chemistry, medicine and health
Agricultural science and industrial technology
Computer technology and Construction Engineering
Children's books
New Year picture calendar
Imported books
periodical
Opera sketch\
These are the categories of Xinhua bookstore
If you want to write social classifications according to the classification of books:
The categories of the book
Then write about the status of this book in the society. For example, classic works: you can write who is proficient in history and Chinese history
3. Be careful not to deviate from the topic
How many kinds of books are there in Xinhua bookstore?
Classics, philosophy, social science, politics, law, military science, financial management, historical geography, culture and education, primary school education, junior high school education, language, Chinese literature, foreign literature, music, art sculpture, photography, drama, calligraphy, seal cutting, nature
The classification system of the library (according to the Chinese library book classification): books are divided into () major categories and () small categories
The Chinese library classification is divided into 5 basic categories and 22 major categories. A mixed number of Chinese phonetic alphabet and Arabic numerals is adopted. A letter represents a large category. The order of the major categories is reflected in the alphabetic order, and the number is used to mark after the letter
Mr. Wang spent 116 yuan in the Xinhua Bookstore to buy selected fairy tales and scientists' stories. How many copies of these two books have you bought?
Let's say that if you buy x copies of selected fairy tales, the amount of money needed is 20x yuan, and the amount of money needed for y copies of "scientist's story" is 8y yuan,
20x+8y=116，
5x+2y=29，
So y = 2, x = 5 or y = 12, x = 1,
Two of the "selected" and "scientists" stories
Mr. Wang spent 116 yuan in the Xinhua Bookstore to buy selected fairy tales and scientists' stories. How many copies of these two books have you bought?
Let's say that if you buy x copies of selected fairy tales, the amount of money needed is 20x yuan, and the amount of money needed for y copies of "scientist's story" is 8y yuan,
20x+8y=116，
5x+2y=29，
So y = 2, x = 5 or y = 12, x = 1,
Two of the "selected" and "scientists" stories
Mr. Wang bought "selected fairy tales" and "scientists' stories" in Xinhua Bookstore for 116 yuan, with 2
This question is not complete. There are 5 selected fairy tales, 2 scientists' stories, 3 fairy tales and 7 scientists' stories. There should be a relationship between fairy tales and scientists' stories. For example, there are several times more fairy tales than scientists' stories, or more than scientists' stories, If you don't spend enough money, there will be enough answers
Teacher Wang bought fairy tales and science stories for 116 yuan. Fairy tales cost 20 yuan and science stories 8 yuan. How many copies did you buy each?
Are there only these conditions? If you are sure that all the conditions are complete, there should be many answers to this question... For example, 1 fairy tale, 12 science stories, 3 fairy tales, 7 science stories All right
There are 6 people in fairy tales and 8 yuan in I love science. Mr. Li has 50 yuan with him. How many copies of these two books can he buy and just run out of money?
I love science 4 and Fairy Tales 3
6*3+8*4=50
I don't know how to put parentheses [this substitute, [- 1 / 12] divided by [1 and 1 / 2 + 1 and 1 / 6-1 and 1 / 12] - 2 * 3 * [- 4] - 6 * [- 5] * [- 7], please write the procedure,
-1/12÷(3/2+7/6-13/12)+24-210
=-1/12×12/19-186
=-1/19-186
=-1/19-3534/19
=-3535/19
I think so, but I'm not sure
Li Guotao's living room is a square with an area of 28 square meters. Please judge whether the side length x of this square living room is rational and why? If the error requirement is less than 0.1 M, what is the value of side length x?
Side length x=
28=2
7 is an irrational number,
Two
7≈5.3m．
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