![](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>)
A car drove from city a to city B and arrived in six hours. When it returned, it speeded up and traveled 8 kilometers more per hour than before. As a result, it took only five hours. How many kilometers is the distance from city a to city B?
A: the distance from city a to city B is 240 km
After 2.5 hours, the passenger car exceeds 12.5 km. The passenger car travels 97 kilometers per hour
How many kilometers per hour can a car travel?
Set up a car to travel x kilometers per hour
2.5(x-97)=12.5
X-97=5
X=102
A: cars travel 102 kilometers per hour
The bus goes from place a to place B at the speed of 80 km / h. one hour later, the car starts from place a to catch up with the bus at the speed of 120 km / h
Let t be the time, and let t be the time
80(t+1)=120t
t=2
Which can be calculated directly without equation
RELATED INFORMATIONS
- 1. Is it right to count 120 km eastward as + 120 km eastward and 80 km westward as - 80 km?
- 2. For the sake of safety, the necessary distance should be kept between the vehicles driving on the highway. It is known that the maximum speed limit of a certain highway is v = 120km / h. assuming that the vehicle in front stops suddenly, the time (reaction time) t between the driver of the rear vehicle and the vehicle starting to decelerate after operating the brake is 0.5s, and the resistance F of the vehicle during braking is 0.4 times of the vehicle gravity, then the high-speed highway will stop What is the minimum distance s between cars on the road?
- 3. It is known that the maximum speed of an expressway is v = 120km / h. assuming that the vehicle in front stops suddenly, the driver of the vehicle behind finds this situation, operates the brake and arrives at the vehicle The time to start deceleration (i.e. reaction time) t = 0.50s, the magnitude of vehicle resistance when braking is 0.40 times of vehicle gravity, what is the minimum distance s between vehicles on the expressway? (gravity acceleration g is taken as 10m / S2) If f = am, how does f / a come from
- 4. The distance between a and B is 80 km. Three hours after a bus leaves a place, a car starts from a place. Its speed is three times that of the bus. It is known that the car arrives at B place 20 minutes later than the bus. Find the speed of the two cars
- 5. For the sake of safety, the necessary distance should be kept between the vehicles driving on the highway. It is known that the maximum speed limit of a certain expressway is v = 120km / h. suppose that the vehicle in front stops suddenly due to fault, and the driver in the rear stops suddenly after discovering this situation, The time (reaction time) t = 0.50s. When braking, the resistance F of the car is 0.40 times of the gravity of the car. What is the safe distance between cars on the highway? (take the acceleration of gravity g = 10m / S ^ 2, the calculation result is in M unit and kept to an integer
- 6. If the acceleration is reduced to 48 km / h in 5 seconds, what is the average acceleration of deceleration linear motion? What is the annoying direction of acceleration?
- 7. A passenger train is 200 meters long and a freight train is 280 meters long. They run in opposite directions on parallel tracks. After 15 seconds from meeting to leaving at the end of the train, the speed ratio of the passenger train to the freight train is lower 5: 3. Ask how many meters each car travels per second
- 8. A passenger car and a freight car run in the same direction on the parallel track. The length of the passenger car is 220 meters, and the length of the freight car is 320 meters. The sum of the speed of the passenger car and the freight car is 32 meters per second. Now the passenger car catches up with the freight car from behind. If the time of the two cars crossing is 1 minute, the speed of the two cars can be calculated
- 9. The distance between the two places is 100 km. The two cars run from the two places at the same time. They meet in four fifths of an hour. The speed ratio of the two cars is 3:2. Does car a travel every hour? The second car runs? Km per hour
- 10. A and B trains leave from both places at the same time. Train a travels 50 kilometers per hour and train B 60 kilometers per hour. When the two trains meet, train a travels 300 kilometers, How many kilometers are there between the two places
- 11. How long does it take for a car to travel 45 kilometers per hour from Jiacheng to Yicheng, arrive in 4 hours, and return with a 20% increase in speed
- 12. A. B is 875 kilometers away from the two cities. A and B leave each other at the same time. A runs 90 kilometers per hour. After 5 hours, the two cars meet. B runs 90 kilometers per hour How many kilometers to drive? Use the equation and tell me before 18:30,
- 13. Math problem: 135 kilometers for slow train in 3 hours and 120 kilometers for fast train in 2 hours!
- 14. There is a small station every 10 kilometers on the railway line from city a to city B. one slow train runs from city a to city B at the speed of 45 kilometers per hour at 9:00 a.m., and the other fast train runs from city a to city B at the speed of 60 kilometers per hour at 9:30 a.m How far should the train stop at the small station from city a at the latest to let the express pass? At least how long does the local train take? (the length of fast and slow trains is ignored)
- 15. A car at a certain speed from city a to city B can reach 5 hours. After 3.5 hours from city a, the car is 90 kilometers away from city B. how many kilometers are there between city a and city B?
- 16. When a car goes from city a to city B, it travels 30 kilometers per hour when going and 25 kilometers per hour when returning. What is the speed ratio between going and returning___ At the same time, the distance ratio is___ What is the time ratio between the two cities___ ．
- 17. From city a to city B, it takes 10 hours for car a and 8 hours for car B. the speed of car a is 25% slower than that of car B () a and 80% slower than that of car B
- 18. It is known that a's speed is 45 km / h, and B's speed is 30 km / h. After all, B's speed immediately returns to meet B's. So, how much did a's speed go from starting to meeting? It's a linear equation of one variable
- 19. A bus from a city to B city, 1 hour 15 minutes 100 kilometers, with the same speed again 3 hours 45 minutes, to B city How many kilometers are the two cities apart?
- 20. If the speed of a car from place a to place B is increased by 20%, it can arrive one hour earlier than the original time. If the speed is increased by 25% after driving 120 km at the original speed, it can arrive 40 minutes earlier______ Kilometers