![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
1 yuan twice applied question 3 There are 132233 natural villages. 2315 ecological civilized villages were built in 2005. It is planned that the number of ecological civilized villages will reach 24.4% of the total number of natural villages by 2007. According to this plan, what is the average annual growth rate of ecological civilized villages from 2005 to 2007?
In 2005, ecological civilized villages accounted for 2315 △ 132233 = 1.75% of the total number of natural villages
From 2005 to 2007, the average annual growth rate of ecological civilization village is X
1.75%（1+x）（1+x）=24.4%
（1+x）=3.73
x=2.73=273%
Column one yuan quadratic solution application problem!
A 2-mead-wide circular road is paved around a circular painting circle. The total area of the road and the painting circle is 200 square meters. How many meters is the perimeter of the center line of the road?
The radius from the center of the circle to the outermost side is under the root sign (200 / 3.14)
The radius of the center line of the corridor is (200 / 3.14) - 1
The perimeter of the center line of the corridor is 6.28 * [under root (200 / 3.14) - 1] = 6.28-6.28 under root 20
=43.84m
How to solve practical problems with one variable quadratic (the best)
I know how to solve one yuan twice, but I know how to solve practical problems!
If you can't solve the equation directly, you'd better use the formula
RELATED INFORMATIONS
- 1. Help me solve the application problem of one yuan twice, fast! A school invested 20000 yuan in laboratory equipment last year, and the total investment is expected to be 120000 yuan this year and next. What is the average growth rate of the investment in laboratory equipment? 2. The profit of a shopping mall in Shanghai is 1 million yuan in July and 1.21 million yuan in September. The profit of B shopping mall in Shanghai is 2 million yuan in July and 2.88 million yuan in September. Which shopping mall has a larger average monthly increase rate It's a process
- 2. Several physics application questions are urgent! 1. The length of an aircraft carrier is 160 meters, and the take-off speed of an aircraft is 40 m / s (1) What is the minimum acceleration for an aircraft to start taxiing at a uniform acceleration on the runway and then take off? (2) If only one aircraft is allowed to taxi on each runway, how many aircraft can take off at most per minute? 2. The normal running speed of the train from station a to station B is 60km / h. once the train started from station a, because it was delayed for 5min, it had to speed up, so that when the average speed was 72km / h, it could just arrive at station B on time, and the movement of the train was set as a straight line (1) What is the normal running time of the train from station a to station B? (2) What is the distance from station a to station B? 3. There are two people, a and B. A is 90m to the south of B. they are moving in a straight line at the same time. A is driving to the east at the speed of 2m / s, and B is driving to the south at the speed of 3m / s. The distance between the two people is calculated after 20s The answers to the questions in the reference book are missing
- 3. Urgent! Ask two high acceleration physics application questions! 1. Party A and Party B start to make uniform acceleration linear motion from the agreed place, in which party a always reaches the end point with the same acceleration, while Party B changes to uniform linear motion after the acceleration reaches the general distance, and Party A and Party B just reach the end point at the same time, what is the acceleration ratio of Party A and Party B? 2. The parachute diver can open the parachute only after leaving the plane for a certain distance from 350m altitude. After the parachute is opened, the parachute diver can decelerate uniformly and move vertically with the acceleration of 2m / S ^ 2, and the speed when reaching the ground is 4m / s. The free falling distance of the parachute diver can be calculated To have a problem-solving process, if you can, please attach a little explanation
- 4. Ask a physics calculation problem in grade one of senior high school A car is driving at a speed of 54km / h along a straight road at a constant speed. At a certain moment, the driver sees the red light in front of him and starts to brake. The acceleration when braking is known to be 5 / S2. As a result, the car just stops at the warning line of the red light (1) The total time that a car can move forward after braking (2) The distance from the warning line when the car starts to brake
- 5. Throw an object horizontally at the initial velocity of VO = 10m / s, and after flying for a period of time, vertically hit the inclined plane with an inclination of 45 ° to calculate the time for the object to complete the flight. (g takes 10m / S2)
- 6. On the calculation of specific heat capacity, those with high attainments in this field come to save me After the iron mass of 100g is heated in the furnace for a long time, it is taken out and immediately put into the cup containing 200g water. The temperature of water rises from 15 ° to 59 ° and the temperature of the furnace is calculated regardless of the heat absorbed by the cup and the heat lost into the air (warm tips: the specific heat capacity of water is 4200j / (kg ° C), the specific heat capacity of iron is 460j (kg ° C). I feel confused. I don't know how to do it. Help me
- 7. Iron is an indispensable trace element for human beings. Normal people should supplement about 14 mg of iron every day, most of which come from food. If all of them take tablets containing FeSO4 · 7H2O to supplement iron, they need to take tablets containing FeSO4 · 7H2O every day______ The content of Fe2 + in a ferrous sulfate tablet on the market is 16.0%. The Fe2 + in the tablet is easy to deteriorate in the air, and the state stipulates that the tablet can not be taken if the Fe2 + deteriorates more than 10.0%. In order to test whether the ferrous sulfate tablet sold in a drugstore is ineffective, 10.0g of the tablet is determined to contain 1.52g of Fe2 +?
- 8. In order to determine the content of sodium carbonate in edible flour soda, Li Tong designed and carried out the following experiments: 1. Weigh 3.4g flour soda sample in a beaker, add 20ml water and stir until the sample is completely dissolved; 2. Add enough CaCl2 solution to it until no precipitation is formed; 3. Filter and remove the precipitate After drying, the weight is 3.0g (regardless of the mass loss in operation). Please calculate: what is the mass fraction of Na2CO3 in edible flour alkali? (accurate to 0.1%)
- 9. Calculation of chemical reaction This question has never been understood A. When B and C are 16 grams, they can only produce 30 grams of new substance D. if 10 grams of a is added, only C remains in the original substance after the translation stops 1 -- after the first reaction stopped, B remained 9g 2 -- after the second reaction, the mass of D is 50g 3 -- the mass ratio of a and B in the reaction is 3:2 4 -- the mass ratio of a to C in the reaction is 5:2 Please analyze each option carefully
- 10. Equilibrium condition of chemical reaction My knowledge of chemical equilibrium conditions is very disordered, such as raising temperature, increasing pressure, and moving chemical equilibrium to which side. I will thank you very much for the tips I have learned
- 11. Known to do some work, a to a day to complete, B to B days to complete, how many days to complete the cooperation between the two?
- 12. When the correspondent chases from the end of the team to the front of the team, he runs at full speed, which is three times faster than the team. When he returns from the front of the team to the end of the team, he reduces 100 meters per minute. In the process of the team moving forward, the correspondent goes back and forth three times in a row to perform the task, and the time spent on the way is 1 hour in total, among which the time spent on three times to go back and forth to the end of the team is 12 minutes less than the time spent on three times to chase the front of the team, The length of the team is______ ．
- 13. How to solve these problems 1/a+3-6/9-a^2 (a/a-b-b/b-a) ·ab/a+b (1/x+1-x+3/x^2-1)/1/x-1 [2/3a-2/a+b(a+b/3a-a-b)]/a-b/a
- 14. Several junior high school calculation problems -1 / 10 by 11 - 1 / 11 by 12 - 1 / 12 by 13. - 1 / 19 by 20 -1/2 - 1/6 - 1/12 - 1/20 - 1/30 - 1/42
- 15. Basic answering process of junior high school physics calculation questions
- 16. Scientific calculation in junior high school (electric energy) A common table lamp with adjustable brightness (the bulb is marked with the words "220 V, 25 W") adjusts the brightness of the table lamp through a knob type sliding rheostat. If the power of the table lamp changes between 16 W and 25 W in the process of adjusting the sliding rheostat, then: (1) what is the maximum resistance of the sliding rheostat? (2) how many degrees of power consumption does each table lamp normally work for 2 hours in a month (30 days)? PS：..
- 17. When a 1W small bulb lights normally for 1 minute, the power consumption is
- 18. On the physical application of internal energy It is convenient and environment-friendly to use the gas stove. When the general gas stove works normally, it can make 4kg, 23 ℃ water boil in 15 minutes (the boiling point of water in this city is 93 ℃) (1) Heat absorbed by water (2) If the gas stove gives out 65% of the heat Please write down the process of solving the problem, The sixth power of 2936 x10
- 19. Xiao Ming once again used the density of 1.5 * 10 ^ 3kg / m ^ 3 rubber for shipbuilding competition, the volume of rubber he used was 20cm ^ 3, resulting in the maximum displacement volume of the boat is 200cm ^ 3. G = 10N / kg. P water = 1 * 10 ^ 3kg / m ^ 3? Write as many as you know, publicity
- 20. The calculation of physical electric power 1. When the "220 V 40 W" and "220 V 60 W" electric lamps are connected in series in a 220 V circuit, their actual power is calculated 2. With the improvement of people's living standards, refrigerators have entered thousands of households. It is known that the rated power of a household refrigerator is 120W, and the working time of the refrigerator is not continuous. If the total working time of the refrigerator is 6h, how many kilowatt hours of electricity is consumed 3. Resistance R1 = 4 ohm, R2 = 8 ohm in series in the 24 V circuit, at this time, the electrical power of R1? 4. An electric iron needs a certain preheating time before it is used, so people often connect it to the power supply when it is not in use, which not only wastes electricity, but also causes the iron head to be oxidized and not easy to be stained with zinc. Xiao Ming connects an electric iron marked "220 V 55 W" with a bulb (the resistance of the bulb in the preheating state is 495 Ω) to form the circuit diagram as shown in the figure, The soldering iron soon reaches the welding temperature What is the power consumption of electric iron in 1 'preheating state The power consumption of the whole circuit in 2 'preheating state is several percent of that of the electric iron in normal operation ——————Electric soldering iron—— ↑ | 220V ___ Switch__ | ↓ | | | ————- light bulb————