![](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>)
The speed of a and B is 15km / h and that of B is 10km / h. Q: after how long, the distance between a and B is 25km?
Solution & nbsp; suppose that after XH, the distance between a and B is 25km. When a and B are 25km apart before meeting, according to the meaning of the question: 15x + 10x = 50-25, the solution is: x = 1; when a and B are 25km apart after meeting, according to the meaning of the question: 15x + 10x = 50 + 25, the solution is: x = 3
Party A and Party B start from M. the speed of Party A is 10km / h. Party A starts 2 hours before Party B starts. The speed of Party B is 15km / h
Can b catch up with a in a few hours?
Suppose B can catch up with a in X hours
15x=2*10+10*x
5x=20
X = 4 hours
The speed of a is 17.5km/h, and that of B is 15km / h. After a few hours, the distance between them is 32.5Km?
There are two situations in this problem: the first time is 32.5Km apart, let's say that after X hours, two people are 32.5Km apart, according to the meaning of the problem: (17.5 + 15) x = 65-32.5, the solution is: x = 1; the second time is 32.5Km apart, let's say that after X hours, two people are 32.5Km apart, according to the meaning of the problem: (17.5 + 15) x = 65 + 32.5, the solution is: X
A and B ride bicycles from a to B at the same time. A's speed is 10km / h. If a arrives 10 minutes earlier than B, how far is the distance between a and B?
A and B ride bicycles from a to B at the same time. The speed of a is 15km / h, and that of B is 10km / h. If a arrives 10 minutes earlier than B, how far is the distance between a and B?
Let the whole process be X
X÷10-X÷15=1/6
3X/30-2X/30=5/30
3X-2X=5
X=5
RELATED INFORMATIONS
- 1. On the map with a scale of 1:2000000, the distance between Jinan and Yantai is measured to be 3.6cm. If the speed of the car is 30km / h, it will leave at 9am When is the time to start from the South and finish the journey to Yantai?
- 2. From Jinan to Beijing, the actual distance is 490 km. The distance between the two places measured on a map is 4.9 cm
- 3. It is stipulated that the speed of a vehicle should not exceed 70 km / h on a certain highway. When a traffic accident occurs, the traffic police usually estimate the speed of the vehicle according to the sliding distance of the wheel after braking. The empirical formula used is v = 16 √ DF, where V is the vehicle speed (unit: km / h), D is the sliding distance of the wheel after braking (unit: m), and F is the friction factor, D = 20m, f = 1.2m, did the speed of the car exceed the specified speed?
- 4. If the speed of car a and car B is equal, and the car decelerates evenly after braking, then the distance of car B is () A. 9 mB. 18 mC. 36 mD. 72 m
- 5. After braking at the same time, the two vehicles of a and B are moving in a straight line with uniform deceleration. A stops for 3 seconds and advances for 36 meters. B stops for 1.5 & nbsp; s. The forward distance of B is () A. 9 mB. 18 mC. 36 mD. 27 m
- 6. After braking, a stops 36m ahead within 3S, and B stops after 1.5s, then B advances
- 7. When a runs to the finish line, B is 10 meters away from the finish line. If a's starting line retreats 10 meters, the two race again at the same speed Who gets to the finish line first?
- 8. In the 100 meter race between a and B, when a reaches the finish line, B is still 10 meters away from the finish line. If a retreats 10 meters from the starting point, who will reach the finish line first?
- 9. A and B practice the 100m race. They start from the starting point at the same time. A's speed is 7m / s, B's speed is 6.5m/s. After running for 10s, a sprained his foot, If the velocity is reduced to 6m / s, can b catch up with a before reaching the 100m terminal? The solution of one variable linear equation is used,
- 10. A train can travel 80 kilometers per hour. How many hours and minutes does it take for this train to travel 50 kilometers?
- 11. A classmate wanted to use the knowledge of circular motion he had learned to measure the speed of his bicycle. When he was riding on a straight road, he recorded it with a stopwatch In a period of time t, the pedal turns K circles, then Write the expression of the forward speed of the bicycle
- 12. After 2 hours, B starts from the same place by bike and pursues a along the same road A. take aerobic exercise at the speed of 5 km / h. After 2 hours, a B starts from the same place by bicycle and pursues a along the same road. According to their agreement, B can catch up with a no earlier than 1 hour and no later than 1 hour and 15 minutes. Please set a speed for B and the speed is positive
- 13. A runs at the speed of 5km / h. After 2 hours, he starts from the same place and follows the same road to catch up with A. but they agree that B should catch up with a no later than 1 hour and no later than 1 hour and 15 minutes. How to determine the speed range of B's car? (use the equation)
- 14. When traveling between a and B, the speed from a to B is 45km / h, and the speed when returning from the original road is 60km / h, Based on the above information, please put forward a problem and use the equation to solve the problem
- 15. (1) if car a starts from a certain place at a speed of 60km / h, write down the distance S1 (km) and its speed A and B trucks are driving on a highway at a constant speed. (1) If car a starts from a certain place at a speed of 60km / h, write the functional relationship between its driving distance S1 (km) and its driving distance t (H), and draw his image. (2) if car B starts from the same place 2 hours after car a starts and drives along the same direction at a speed of 80km / h, its driving distance S2 (km) is also a function of the driving time t (H) after car a starts, write its driving distance S2 (km) (3) find out the coordinates of the intersection of two images, and explain the practical significance of the coordinates of the intersection
- 16. A car runs one third of the distance on a straight road at the speed of V1 = 40km / h, and then runs the whole distance at the speed of V2 = 20km / h Seek the average speed of the whole process
- 17. The highway from Xi'an to Hanzhong is about 288 kilometers long. The two cars leave each other from the two places. Three hours later, the distance is 18 kilometers. If car a travels 48 kilometers per hour, how many kilometers does car B travel per hour
- 18. A and B leave from both places at the same time. A travels 45 kilometers per hour, while B drives 8 / 9 of the speed per hour. After four hours, the two cars go to the same place How far is the distance between a and B
- 19. A. The highway between B is 680 km long. Two cars drive from both places at the same time. Car a travels 35 km per hour, and car B's speed is 1.3 times that of car A. after several hours, they meet each other
- 20. Xiao Ming was running on the road one day. He found a thing. The bus in front of him comes every ten minutes on average, and the bus behind him catches up with one every fifteen minutes on average. How many minutes does the bus stop send the bus on average