1.A and b two cars leave from two places 280 kilometers apart at the same time, and the distance of two and a half hours is 25 kilometers. Car A is 52 kilometers per hour, how many kilometers more than car B?

2. The ratio of the number of construction teams A and B is 5:3. If Team A sends 15 people to Team B, the ratio is 3:2. What is the original number of two engineering teams, A and B?

Party A and Party B plan to produce 7000 parts a month. Actually, Party A overfulfilled my plan by 25%, and Party B produced 500 sets more than my plan. After this production, two people * * * produced more than planned 1500. B How many such parts have actually been produced this month?

Xinhua Bookstore opened at 8: 00 in the morning, Xiaogang left home for the bookstore at 7: 20, and at 7: 40, he walked 5/8 of the whole journey. At this rate, when will he arrive at the bookstore?

5. On Arbor Day, the sixth-grade students in a school went to plant trees. The number of boys participating in tree planting is twice that of girls. Boys plant 4 seedlings on average, and girls plant 1 seedling on average. How many trees did the students involved in tree planting plant on average?

Please calculate the formula.