2. One person copies the manuscript for 5 hours, and one person copies it for 4 hours. How many hours does it take two people to copy together?
3. A project will be completed by the teams of Party A and Party B in 5 days, with one person from Party A 15 days and one person from Party B for several days?
4. To complete a project alone, the master needs 12 hours, which is 3 hours faster than the apprentice. If the master and the apprentice work together, how many hours can you complete the task?
5. It takes 15 days for Party A to complete a project alone, and 6 days for Party B to complete the whole project. How many days can Party A and Party B work together?
6. For a project, it takes 10 days for Party A to do it alone, and 12 days for Party B to do it alone. How many days can Party A and Party B work together?
7. For a project, it takes 15 days for Party A to do it alone, 20 days for Party B to do it alone and 5 days for Party A and Party B to do it together. How much is left in this project?
8. It takes Party A 8 hours to copy a manuscript by one person, and Party B needs 12 hours. If Party B copies it for 3 hours first, how many hours will it take Party A and Party B to copy the rest together?
9. For a project, it takes 15 days for Party A to do it alone and 12 days for Party B to do it alone. After Party A and Party B have worked together for 3 days, how much is left in the project?
10. A single project takes 10 days to complete, two days less than team B and five days less than team C. If three teams work together, how many days can it be completed?
1 1. For a project, team A will do it alone for 6 hours, team B will do it alone for 8 hours, and team C will do it alone 12 hours. If three teams cooperate, how many hours will it take to complete the whole project?
12. It takes 18 days for Team A to do a project alone, 24 days for Team B to do it alone, and 8 days for both teams to do it together. How many days will it take Group A to finish the rest of the project alone?
13. It takes 20 days for Master Wang to make a batch of parts, 30 days for the apprentice and 8 days for the master-apprentice cooperation. How many parts are left in this batch?
14, master and apprentice process a batch of parts, the master processes them separately for 8 hours, and the apprentice processes them separately 10 hour. How many hours does it take for the master to process with the apprentice after 2 hours?
15, a highway, a construction team to repair alone, it takes 8 days to complete; It takes 12 days for Team B to maintain alone. After the two teams repair together for four days, the remaining tasks will be completed by team A alone. How many days will it take?
16, a water reservoir, filled with single open pipe 10 hour, single open pipe 12 hour, single open pipe 15 hour. After the pipes A and B are opened at the same time for 4 hours, they are closed, and then the pipe C is opened. How many hours does it take for pipeline C to fill the pool?
17. A manuscript is copied by one person, Party A 10 hour, Party B 12 hour, and Party C 15 hour. Now it takes four hours for one person to copy, and the remaining two parties each copy one. How many hours will it take to finish the quarrel?
18, build a wall, one team can work alone for 3 days, and the second team can work alone for 4 days. According to this calculation, how many days will it take two teams to finish the wall together?
19. The distance between Party A and Party B is 19 km. Xiaoguang and Daming travel from two places at the same time. Xiaoguang travels 4 kilometers per hour and Daming travels 5.5 kilometers per hour. Xiaoguang returns to Party A as soon as he arrives at Party B, and Daming returns as soon as he arrives at Party A.. They met a few hours later on their way back.
20. It takes four hours for a bus to go from A to B, and six hours for a truck. If two trains leave from two opposite directions for several hours at the same time, will they still be separated from each other?
2 1. Party A and Party B build a wall. It takes 6 days for Party A to build the wall alone, and 12 days for Party B to build the wall alone. Now, after 3 days, the rest will be done by both parties. How many days will it take?
22. It is planned to produce a batch of chemical fertilizers. It takes 8 hours to do it alone in one workshop, and it takes 10 hour to sit alone in the second workshop. After six hours of simultaneous production in two workshops, the output will be 700 kilograms more than planned. How many kilograms of chemical fertilizer do you plan to produce?
23. To build an expressway, Team A can complete it in 30 days, while Team B can do it alone, and it can repair 60 meters every day. If two teams work together for six days, all the projects can be completed. What is the total length of this highway?
24. To build a canal, it takes 12 days for Team A to repair it alone, and 18 days for Team B to repair it alone. Now team A has repaired it for two days, and team B has helped to repair it together. How many days did it take to complete the canal?
25. For a certain project, Team A completed it in 8 days, and Team B 12 days. After several days of cooperation between the two teams, the remaining project was completed by Team A in only three days. How many days have you been on the team?
Attachment: Answer
1、 1/( 1/30+ 1/24+ 1/20)=8
2、 1/( 1/5+ 1/4)=20/9
3、 1/( 1/5- 1/ 15)=7.5
4、 1/( 1/ 12+ 1/ 15)=20/3
5、 1/( 1/ 15+ 1/6)=30/7
6、 1/( 1/ 10+ 1/ 12)=60/ 1 1
7、 1-5*( 1/ 15+ 1/20)=5/ 12
8、( 1-3* 1/ 12)/( 1/8+ 1/ 12)=3.6
9、 1-3*( 1/ 15+ 1/ 12)= 1 1/20
10、 1/( 1/ 10+ 1/ 12+ 1/ 15)=4
1 1、 1/( 1/6+ 1/8+ 1/ 12)=8/3
12、 1-8*( 1/ 18+ 1/24)/( 1/ 18)=4
13、 1-8*( 1/20+ 1/30)= 1/3
14、( 1-2* 1/8)/( 1/8+ 1/ 10)= 10/3
15、 1-4*( 1/8+ 1/ 12)/( 1/8)=4/3
16、 1-4*( 1/ 10+ 1/ 12)/( 1/ 15)=4
17、( 1-4* 1/ 15)/( 1/ 10+ 1/ 12)=4
18、 1/( 1/3+ 1/4)= 12/7
19、 19*3/(4+5.5)=6
20、 1-3*( 1/6+ 1/ 12)/( 1/ 12)=3
2 1、 1/( 1/4+ 1/6)=2.4
22. the design is divided into x, (x/8+x/ 10)*6=x+700, and x=2000.
23、 1-6* 1/30=4/5
60 * 6/(4/5) = 450m
24、( 1-2* 1/ 12)/( 1/ 12+ 1/ 18)=6
6+2=8
25、( 1-3* 1/8)/( 1/8+ 1/ 12)=3