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Aunt Li sells two pieces of clothes for 84 yuan. One of them makes a profit of 20% and the other loses 20%. Is Aunt Li making a profit or a loss when she sells these two pieces of clothes ()
Youyou, President system,
The original price of the profitable piece is: 84 (1 + 20%) = 70 (yuan)
The original price of the loss piece is: 84 (1-20%) = 105 (yuan)
The actual price is less than the cost: 105 + 70-84 × 2 = 7 (yuan)
So it's a loss!
Aunt Li sells a piece of clothes at the price of 100 yuan, making a profit of 25 yuan, making a profit of ()%
Aunt Li made a profit of 25 yuan (33.33%) when she sold a piece of clothes at the price of 100 yuan
Who can tell me the unit of length and weight in Canada and the United States?
For example, we Chinese generally use meter, decimeter
The weight is Jin and kg
What is their general unit of measurement in their country?
Length: inch, foot, yard, mile
Inch is 2.54 cm
foot =12 inch
yard = 3 foot
mile = 5280 foot
Weight: I don't quite understand
Pound pound = 454 G
ton = 2000 pound
Ounces oz
Pink pink?
The product of two factors is 56. What is the product of one factor multiplied by 4 and the other divided by 2
Product = 56 × 4 △ 2 = 112
The definition field of function y = 1 / x + 2 + radical 4-x & # 710; 2 is () (a) [- 2,2) (b) (- 2,2] (c) (- 2,2)
（D）[-2,2]
c. X is not equal to - 2,4-x2 > = 0
How to convert a ton of liquid oxygen into gas? What is the quantity?
What is the state of your gas? If it is the standard state: 1000 △ 1.429 = 700 standard cubic gas. Other states should be carefully calculated
Outlet state refers to the current pressure and temperature of the medium
(3a-2b) (3a + 2b) calculation
Find the tangent plane of the surface XYZ = 1 so that it is parallel to x + y + Z = 5
Let the tangent point be (x0, Y0, Z0) f (x, y, z) = xyz-1fx = YZ, FY = XZ, FZ = xyn = (y0z0, x0z0, x0y0) because the tangent plane is parallel to the plane x + y + Z = 5, so y0z0 / 1 = x0z0 / 1 = x0y0 / 1, that is, x0 = Y0 = z0x0 & # 179; = 1x0 = Y0 = Z0 = 1, so the tangent point is (1,1), the normal vector is (1,1) and the tangent plane is X-1
Examples of using the transformation method——————————————————
1. The application of "transformation method" in acoustics: we know that the loudness of the sound produced by the sounder is related to the amplitude of the object, but sometimes the amplitude of some objects, such as tables, gongs and drums, is not easy to be directly observed by the naked eye. At this time, we can put a small mass of paper on the table, gongs and drums and other vibrating objects, In this way, the amplitude of the table which is difficult to see is transformed into the amplitude of the paper ball which is easy to see. The amplitude of the paper ball reflects the amplitude of the table, so as to know the loudness of the sound when the table vibrates
2. The application of "conversion method" in Thermal Science: we know that in order to compare the calorific value of two fuels, we compare the amount of heat released by two equal mass fuels when they are completely burned, and the amount of heat released can not be directly measured by measuring tools. At this time, we convert the amount of heat released by fuel when it is completely burned to the amount of water with equal mass when it is heated, And the temperature rise of water can be directly measured by thermometer, so we can use thermometer to measure the temperature change of water of equal mass, so as to compare the calorific value of different fuels
3. Application of "transformation method" in Mechanics: because the effect of pressure, that is, the magnitude of pressure, can not be directly observed by naked eyes, we can transform the magnitude of pressure produced by objects to the degree of hand pain, the size of sponge deformation, the depth of yellow sand subsidence, etc, In this way, we can directly reflect the pressure produced by the object; and when we study the kinetic energy of the object, we can convert the kinetic energy of the object to the amount of work done by the object to the external object (such as wood). Moreover, the more work the moving object does to the wood, the greater the kinetic energy the moving object has, Of course, the "transformation method" is also used to study the gravity potential energy of the lifted object
4. The application of "conversion method" in electricity: when we study the resistance of conductors, we connect different conductors to the two ends of the same power supply, and use an ammeter to see the current in the circuit, so as to know the resistance of different conductors. Moreover, the larger the current in the circuit is, It shows that the resistance of the conductor to the current is smaller; and when we study Joule's law, because the amount of heat generated by the current flowing through the conductor can not be perceived by hand, and there is also the risk of hand scalding, so in the new curriculum reform textbooks, we should seize the matchstick and only when it reaches a certain ignition point can it be ignited, If the amount of heat generated by current flowing through a conductor is converted to who lights the matchstick first, it means that more heat is generated by current flowing through that conductor. Of course, when Joule's law is studied, the amount of heat generated by current flowing through a conductor can also be converted to heating water of the same mass, Observe the temperature change of water with thermometer to know the heat generated by current flowing through conductor
It is known that a, B and C are the opposite sides of ∠ a, B, C in △ ABC, respectively. The equation a (1-x ^ 2) + 2bx + C (1 + x ^ 2) = 0 about X has two equal real roots, and 3C = a + 3B,
(1) Judging the shape of △ ABC
(2) Find the value of sina + SINB
The equation is (C-A) x ^ 2 + 2bx + (c + a) = 0
Discriminant = 4B ^ 2 + 4 (C ^ 2-A ^ 2) = 0
So C ^ 2 = B ^ 2 + A ^ 2
The triangle ABC is a right triangle
And 3C = a + 3B
So (a + 3b) ^ 2 = 9 (a ^ 2 + B ^ 2)
A: B: C = 3:4:5
sinA+sinB=7/5
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by AISPs
RELATED INFORMATIONS
- 1. Today, Aunt Li's clothing store sold two pieces of clothes at the same time, each at 96 yuan. One of them earned 20% and the other lost 20%. Did Aunt Li make or lose money on these two pieces of clothes? How many yuan did she make or lose?
- 2. I bought a story book?
- 3. University, recommend an English story book In a quiet place, there are many English story books. Instead of Chinese and English, the content of the book is just warm stories. In the past, Bertelsmann had a lot of them, but I don't remember their names. I just want to find a book with concise cover and philosophical stories similar to Bertelsmann's,
- 4. Science and technology books account for 40% of the total books in the school library, and story books account for 30% of the total books. There are 1200 more science and technology books than story books?
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- 6. He often goes to the library to consult reference books, dictionaries and (Modern Chinese Dictionary) to correct mistakes
- 7. I'd like to ask a question: Xiao Fang and Xiao Ming went to Xinhua Bookstore to buy modern Chinese dictionary. Xiao Ming said, "I'm not good at buying this dictionary with my money 26 yuan. "Xiaofang said," I'm still 14 yuan short of this dictionary. "It's known that the sum of their money is just enough to buy this dictionary. How much is the price of this dictionary?
- 8. After Mr. Chen bought the prizes for the sports meeting for the school, he went back to the school and handed over the account to Mr. Wang of the logistics department, saying: "I bought two kinds of books, 105 copies in total, with the unit price of 8 yuan and 12 yuan respectively. Before I bought the books, I received 1500 yuan, but now I still have 418 yuan left." Mr. Wang calculated and said, "you must be wrong." why did Mr. Wang say he was wrong? Try to explain with the knowledge of equation
- 9. The school library bought 12 bags of books, 4 books in each bag. Each book costs 25 yuan. How much did it cost to buy these books?
- 10. Late at night, around () came down, Lingling () sat next to teacher Li, looking at teacher Li () face, feeling sad I can't do it for a long time
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- 14. Fruit Aunt Li brought some apples and pears. The mass ratio of apples and pears is 3:1. Apples are 120kg more than pears. How many kilograms are there in total?
- 15. A barrel of oil weighs 50kg. When it is half finished, the barrel weighs 26kg. How many kilos of oil and barrel?
- 16. Aunt Li bought 2kg eggs and 10kg rice for 88.6 yuan, while Aunt Wang bought the same eggs and rice for 0.5kg Formula
- 17. Aunt Li bought 15kg of special flour and 35kg of rice for 97.5 yuan. The price of 1kg of special flour is twice that of 1kg of rice. How much is the price of 1kg of special flour and rice?
- 18. Aunt Deng bought 2kg tomatoes per kilogram a yuan and 1.5kg cucumbers per kilogram B yuan A-B means?
- 19. Aunt Li bought 2 kg of apples and 2 kg of pears, which cost 20 yuan in total. It is known that 4.4 yuan per kg of pears, and how much is it per kg of apples Lie equation
- 20. Aunt Wang bought a total of 42.2 yuan of fruit. She bought 8 kg of apples. The unit price of apples is 3.25 yuan, and that of bananas is 4.50 yuan. How many kg of bananas do you buy?