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 every hour. After four and a half hours, car A arrives at the West Station without stopping, and immediately returns from the original road, and meets car B at a distance of 31.5km from the West Station. How many kilometers does car A travel per hour?
3. Two people ride bicycles along a 900-meter-long circular track. They traveled in opposite directions from the same place, so they met once in 18 minutes. If they drive in the same direction, and the fast train catches up with the slow train once in 180 minutes, how fast can they ride bicycles?
4. The distance between Party A and Party B is 360 kilometers, and buses and trucks leave from Party A for Party B at the same time. The speed of the truck is 60 kilometers per hour and the speed of the bus is 40 kilometers per hour. After the truck arrives at the second place, it stays for 0.5 hours and returns to the first place at the original speed. A few hours after starting from the first place, the two cars met.
5. The express train and the local train leave from Party A and Party B at the same time, and meet in 12 hours. After the encounter, the express train took another 8 hours to reach B, and how many hours did the local train take to reach A?
6. The distance between the two places is 380 kilometers. There are two cars leaving from two places at the same time. Originally, car A planned to run at 36 kilometers per hour and car B planned to run at 40 kilometers per hour, but when driving, car A changed speed and left at 40 kilometers per hour. How many kilometers did B car travel less than originally planned when they met?
7. The distance between east and west towns is 240 kilometers. A bus goes from Dongzhen to Xizhen at 8: 00 a.m. and a truck goes from Xizhen to Dongzhen at 9: 00 a.m. At noon, the two cars meet at the midpoint of the two towns. If both cars leave at 8: 00 a.m. with the same speed, how many kilometers are the two cars apart by morning 10?
Water injection problem: 1. A pool has two water injection pipes, A and B. After opening A and B at the same time for 4 hours, the second pipe is closed after 6 hours and filled with water. It is known that the water injection amounts of A and B are the same in 2.5 hours and 2 hours. How many hours does it take to open a and b separately to fill the pool?
Engineering problem: 1. A company completed a project in three stages, the first stage took 40% of the total project time, the second stage took 36% of the total project time and the third stage took 24 days. How many days did it take to complete all the projects?
There are two buckets. The capacity of barrel A is 400 liters, and that of barrel B is 150 liters. If the water discharged from barrel A is twice as much as that from barrel B, and the remaining water in barrel A is four times as much as that from barrel B ... How many liters of water is released per barrel?
There are two plugs in the water tank. Pull off the first plug, and the water in the water tank will flow out after 5 minutes. Pull the second plug and it will flow out in 7 minutes. If the two plugs are pulled out for 2 minutes, a * * * will drain 1200 liters, and then plug in the first plug. How long does it take to drain the water in the tank?
It will take two hours for Party B to finish the rest after Party A finishes half of the tasks. If Party A completes the remaining tasks after 3 1, it will take two people * * * 1 hour for 50 minutes. How many hours does it take for Party A and Party B to complete?
A project was originally planned to be completed by 270 workers in a few days. There are only 200 workers at present. As the work efficiency was increased by 50%, the result was advanced by 10 days. Seek the original planned working days?
6. The lathe shift originally planned to produce 50 parts every day. After improving the operation method, in fact, six more parts are produced every day than originally planned. The result was 5 days ahead of schedule, exceeding 8 parts. How many parts did the lathe shift originally plan to produce?