1. Two cars leave from Party A and Party B at the same time. Car A travels 48 kilometers per hour, and car B travels 54 kilometers per hour. When they met, the two cars were 36 kilometers away from the midpoint. How many kilometers is it between Party A and Party B?
2. The distance between A and B is150km. Two trains go from a to b at the same time. The express train is 60 kilometers per hour and the local train is 48 kilometers per hour. When the express train arrives at B, how many kilometers is the local train from B?
Xiaoming walked 6 kilometers per hour from A to B, 9 kilometers per hour when he came back, and it took him 5 hours to go back and forth. How many kilometers did Xiaoming walk back and forth?
4. A person walks 5 kilometers per hour. If it takes 8 minutes less to ride a bike than to walk every 1 km, how many times faster can he ride a bike than to walk?
When someone travels from city A to city B in a straight line, he travels at a constant speed of 30 kilometers per hour when he goes there, and returns at a constant speed of 60 kilometers per hour when he comes back. What is the average speed of this person going back and forth?
It takes teachers 55 minutes to drive 40 kilometers to school every morning. One morning, she left home seven minutes late, so how many kilometers per hour can she get to school on time as usual?
7.A and B are 56 kilometers apart, and there are three people, A, B and C. A and B start from City A and C start from City B at the same time, moving in opposite directions. A, B and C travel at the speed of 6 km, 5 km and 4 km per hour. How many hours after departure, is B at the midpoint between A and C?
8. The master chased his dog. The dog runs three steps, the master runs two steps, and the master's step is the dog's two steps. After the dog ran 10, the owner began to chase. How many steps did the dog run when the owner caught up with it?
9. Brother and sister are playing by a circular pool with a circumference of 30 meters. They walked around the pool with their backs to the same place at the same time. Brother walks 13 meters per second, and sister walks 12 meters per second. When they met for the tenth time, how many meters did my sister have to walk to get back to the starting point?
10.a and B run back and forth on a straight road, with a distance of 100 meters. A runs 28 meters per second and B runs 22 meters per second. They started from both ends of the straight road at the same time. When they run for 30 minutes, how many times do they meet during this time?