2. The school needs to burn a batch of CDs and go to the computer company to burn them, each 8 yuan; If the school is self-made, in addition to renting a burner, 120 yuan is required, and 2 yuan is required for each CD. Q: When the school needs to burn many CDs, do the two methods cost the same?
3. Two people ride bicycles to train along the circular track. If two people walk back from the same place,/kloc-meet once every 0/8 minutes; If you start from the same place and the same direction, the fastest can catch up with the slow one in 180 minutes. What is their speed?
The distance between Station A and bilibili is 440 kilometers. If an express train and a local train leave from Station A and bilibili at the same time, they will go in opposite directions. It is known that the express train is 65 kilometers per hour and the local train is 45 kilometers per hour. At the same time, a swallow set off with the express train and flew to the local train. When it meets the local train, it turns around and flies to the express train. When you meet an express train, turn around and fly to the local train. Swallows fly 80 kilometers per hour. So, how many kilometers did the swallow fly when the two cars met?
5. Party A and Party B have the same weight. A is 450 yuan, and B is 900 yuan. It is known that B is more expensive than A per kilogram 150 yuan. What are their respective prices?
Observing Objects is a difficult course in the fifth grade of primary school mathematics. So