![](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>)
When a seventh grade student was doing his homework, he accidentally knocked over the ink bottle, so that only the following words could be seen in an applied question: "the distance between a and B is 40km, the speed of motorcycle is 45km / h, and the speed of truck is 35km / h." Please complete this assignment and solve the equation
Let's meet in X hours. According to the meaning of the question: 45x + 35x = 40, the solution is x = 12
When a careless classmate of class 7 (1) of a school was doing his homework, he accidentally knocked over the ink bottle, so that one homework only saw: "the distance between a and B is 160 km, the speed of the motorcycle is 45 km / h, the speed of the truck is 35 km / h, and the speed of the motorcycle is 45 km / h? Please complete this assignment
How many hours does the motorcycle arrive before the freight car when two cars start from place a to place B at the same time?
RELATED INFORMATIONS
- 1. When doing math homework, a student accidentally knocked over the ink bottle, so that only the following words could be seen in an assignment: "a and B are 40 km apart, the speed of the motorcycle is 45 km / h, the speed of the truck is 35 km / h, the truck goes y hours ahead (where y is a constant) how far is the motorcycle from B to catch up with the truck?
- 2. At the new year's sports meeting, the students actively participated in various competitions. It's really (allegorical)
- 3. In order to do a good job in a class activity, the teacher asked the students to give an idea and said a allegorical saying? Fill in the allegorical sayings What about proverbs?
- 4. How to measure 100g alcohol without balance and measuring cylinder?
- 5. If you don't have a balance and a measuring cylinder, how can you measure 100g alcohol
- 6. In order to measure 50g alcohol with density of 0.8g/cm3 at one time, Xiao Ming should choose the best one a.10ml,0.5ml b.50ml,1ml c.100ml,1ml d250ml,5ml Which is it?
- 7. Haibao is the mascot of 2010 Shanghai World Expo, as shown in the picture "Haibao" is the mascot of the 2010 Shanghai World Expo, as shown in the picture. Among the various "Haibao" ornamented on the streets of Shanghai, one is of uniform and solid material, with a volume of 2M and a density of 1.5 × 10 ^ 3kg / m ^ 3 and a contact area of 1m with the horizontal ground; Then (1) what is the pressure of this "Haibao" on the ground? (2) what is the pressure of this "Haibao" on the ground? (g = 10N / kg)
- 8. The volume of the hollow aluminum ball is 30cm3, the mass is 27g, and the total mass is 43g after filling with a certain liquid?
- 9. The volume of the hollow aluminum ball is 30 cubic centimeter, the mass is 27 grams, and the total mass is 43 grams after filling with a certain liquid. The density of the liquid is 2.7 * 10
- 10. The volume of the hollow aluminum ball is 30cm3, the mass is 27g, and the total mass is 43g after filling with a certain liquid?
- 11. A, B and c run around the 300 meter playground. A runs 120 meters per minute, B runs 100 meters per minute, C runs 70 meters per minute. How many minutes will the three meet?
- 12. The distance between a, B and C is 300 meters in turn. A, B and C walk 100 meters, 90 meters and 85 meters in turn every minute. If a, B and C start at the same time, it will take a few minutes The distance between a, B and C is 300 meters in turn. A, B and C walk 100 meters, 90 meters and 75 meters in turn every minute. If a, B and C start at the same time, the distance between a and B is equal for the first time in a few minutes
- 13. The density is 0.6 × 103 kg / m3, and the volume is 100 cm 3. The bottom of the container is tied with a rope, as shown in the figure As shown in Fig. 4, if the water level is just level with the surface of the block when water is injected into the container, the tension on the rope is 0______ Cattle
- 14. 11. A wooden block with a density of 0.6 × 103 kg / m3 and a volume of 100 cm3 is tied to the bottom of the container with a rope, as shown in Figure 4 11. A wooden block with a density of 0.6 × 103 kg / m3 and a volume of 100 cm3 is tied to the bottom of the container with a rope, as shown in the figure 4. When water is poured into the container, the surface of the water is just level with the surface of the wood block, and the tension on the rope is______ Cattle
- 15. There is a brick with a density of 2.5 × 103 kg / m3 and a pressure of 2.45 × 105 Pascal. If the brick is stacked neatly on the horizontal ground which can withstand 2 × 106 Pascal, the brick can be stacked at most______ It's five meters high
- 16. When a cube floats on the water surface and the volume ratio of the upper part to the lower part is 3:7, the density of the block is______ ．
- 17. The weight of root wood is 1600n, the volume is 0.2m3, floating on the water surface, G is 10N / kg, 1 wood density, 2 wood buoyancy, 3 wood drainage volume
- 18. The volume of a block of wood is 100 square centimeters, and the density is 0.6 kg / m2. When the block is placed on the water, what is the buoyancy when it is still? (g = 10N / kg) Wrong number... Change square meter to cubic meter I want the exact number!!
- 19. A student uses a spring dynamometer, stone, thin wire, water and beaker to measure the density of liquid. Design the experimental steps and list the expression of liquid to be measured. Stone density > liquid density, stone density > water density
- 20. The following equipment is available: a solid metal block, a spring dynamometer, thin wire, a large beaker, and an appropriate amount of water, The density of water is known, 2 letter expression of metal block density=