Solution: Suppose two cars meet after driving for x hours.
Then because car A is faster than car B, then 60-55 is the distance that car A travels more than car B per hour.
Therefore, (60-55) x = 45; x=9
It took nine hours from departure to meeting, so the distance between the two places is s=(60+55)*9= 1035km.
2. Both cars of Party A and Party B travel from East Station to West Station at the same time. Car A travels12km more than car B. After driving for 4.5 hours, car A arrives at the West Railway Station and immediately returns along the original road. Meet car b at 3 1.5 km west station. How many kilometers does car A travel per hour?
Solution: You can imagine that A is twice as long as B, 3 1.5km, and it is clear to draw a picture.
Therefore, the total * * * travel time of car A is t=3 1.5*2/ 12=5.25 hours.
Since it took 4.5 hours to reach the West Railway Station, it took (5.25-4.5)=0.75 hours to reach 3 1.5 km after U-turn.
Therefore, the speed of vehicle a is v = 31.5/0.75 = 42km/h.
3. Two cars, Party A and Party B, set off from A and B at the same time, and meet for the first time at a distance of 85km from AT. After meeting, the two cars move on and return immediately after arriving at the station. The second meeting was at a distance of 65 kilometers from B. We calculated the distance between AB and an automobile shop.
Solution: This problem is easy to be bypassed at first glance, but drawing a road map will naturally find the relationship between the back and forth.
Because the speed is constant, the first encounter is the distance between AB points, and the second encounter is exactly twice the distance between AB points. The speed of the two cars is constant, which means that the time spent on the first and second encounters is equal. Therefore, V 1 can be regarded as speed a, V2 as speed b, s as distance, and t as the first meeting time. Four formulas are listed.
v 1 * 2t = s+65; V2 * 2t = 2s-65; v 1 * t = 85; V2*t=s-85
So the distance of AB is s= 105km, and the driving distance of A is V 1*2t=s+65= 170km.
A bus and a truck run in opposite directions from the east and the west at the same time. Buses travel 56 kilometers per hour and trucks travel 48 kilometers per hour. The two cars met at a distance of 32 kilometers from the midpoint. What's the distance between east and west?
Solution: As in the previous question, since it is at the midpoint of 32 kilometers, that is, the bus travels 32*2=64 kilometers more than the truck.
According to the speed difference of 8km/h, it took 8 hours from the beginning to the meeting, so the distance between the two places is s=(56+48)*8=832km.
The distance between a and b is 480 kilometers. Two cars A and B leave from two opposite stations at the same time. Car A travels 35 kilometers per hour and car B travels 45 kilometers per hour. A swallow flies to car B at the same time with car A at a speed of 50 kilometers per hour. When it meets car B, it turns back and flies to car A, when it meets car A, it goes back to car B, and so on. How many kilometers did the swallow fly before two cars met?
Solution: This problem is indeed deceptive, but from the phenomenon, the swallow has been flying, that is, as long as I know how long the swallow has flown, I know how far it has flown.
Judging from the topic, AB is 480km apart, and the speed of A car and B car is known, so it only takes 480/(35+45)=6 hours to meet. So the swallow has been flying from beginning to end, that is, the distance of the swallow is s=6*50=300km.
(1) Two trains A and B run in opposite directions from two places 700 kilometers apart at the same time. The speed of train A is 85 kilometers per hour, and that of train B is 90 kilometers per hour. How many hours do the two trains meet?
Solution: Let's meet in t hours, then 35t+45t = 700;; T=700/(35+45)=8.75 hours
Two trains leave from two stations in opposite directions at the same time. Car A travels at a speed of 48 kilometers per hour, and car B travels at a speed of 78 kilometers per hour. Two and a half hours later, two trains met. How many kilometers is the railway between the two stations?
Solution: If the distance is S km, then s=48*2.5+78*2.5=3 15km.
(3) The two trains, A and B, run in opposite directions from two places 988 kilometers apart at the same time, and meet after 5.2 hours. The speed of train A is 93 kilometers per hour, and that of train B is how many kilometers per hour? Solution: If the speed of car B is V km/h, then 93 * 5.2+5.2V = 988;; V=97
PS: Leave me a message if the landlord doesn't understand, and I will explain it in detail. Seeing that I am working so hard, the landlord will give me some chase.