For a project, it takes 10 days for Party A to do it alone, and 15 days for Party B to do it alone. If two people cooperate, their work efficiency will be reduced. Party A can only complete the original 45, and Party B can only complete the original 910. They need 8 days to complete the project, and the number of days for two people to cooperate is as small as possible. How many days do they have to cooperate?

For a project, it takes 10 days for Party A to do it alone, and 15 days for Party B to do it alone. If two people cooperate, their work efficiency will be reduced. Party A can only complete the original 45, and Party B can only complete the original 910. They need 8 days to complete the project, and the number of days for two people to cooperate is as small as possible. How many days do they have to cooperate?

The number of days of cooperation is x, (110 × 45 + 115 × 910) x (110 × 45 + 115 × 910) x (110 × 45 + 115 × 910) x + 110 × (8-x) (8-x) and the number of days of cooperation is x, (110 × 45 + 115 × 910) x ((110 × 45 + 115 × 910) x (110 × 45 + 115 × 910) x (110 × 910) x + 110 (8-x) x (8-x) as (8-x)) is the first & nbsp & nbsp & nbsp; & & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & & nbsp; & nbsp & nbsp; & & nbsp; & & nbsp; & nbsp; & nbsp; & nbsp & nbsp; & & nbsp; & & nbsp; & & nbsp & nbsp & nbsp; & & nbsp; & & nbsp & nbsp & nbsp; & nbsp; & & nbsp & nbsp & nbsp; & & nbsp & nbsp; & & nbsp & nbsp; & & nbsp & nbsp; & & nbsp & nbsp & nbsp; & & nbsp; & & nbsp & nbsp; & & nbsp; & & nbsp & nbsp & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; &Nbsp; & nbsp; & nbsp; & nbsp; 125x = 15 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X = 5 A: they have to work together for 5 days

For a job, if Party A does it alone in 5 hours, Party B will do it in 3 hours; if Party B does it in 9 hours, Party A will do it in 3 hours
After hours, Party A and Party B will do it together, and it will take several hours
Try to use arithmetic, if you use equation, do not set YZ

The total workload is certain, so there are: 5x + 3Y = total workload = 9y + 3x. It is concluded that: x = 3Y total workload is 5x + 3Y = 18y. A completed 3x in 3 hours alone, the remaining quantity is: 18y-3x = 18y-9y = 9y; a and B work together

For a project, Party A will do it in five hours, and Party B will do it in three hours; Party B will do it in nine hours, and Party A will do it in three hours. How many hours does it take for Party A to do it in one hour?

Because: a 3 hours + B 9 hours can also complete the work, so the remaining workload after a 1 hour is: (a 3 hours workload - a 1 hour workload) + B 9 hours workload, = a 2 hours workload + B 9 hours workload, = B 6 hours workload + B 9 hours workload, = B 15 hours workload A: then it will take 15 hours for Party A to finish the work in one hour

For a job, Party B will do it in 3 hours after Party A does it in 5 hours, and Party A will do it in 3 hours after Party B does it in 9 hours, so Party A will do it in 1 hour,
When can it be completed? Binary linear equation (no, it's better to be one variable or arithmetic)

(9-3)÷(5-3)=3
The efficiency of a is three times that of B. for the same amount of work, B takes three times as much time as a
9 + 3 × 3 = 18 (hours)
If it's all done by B, it'll take 18 hours
18-1 × 3 = 15 (hours)
It takes 15 hours for Party B to do it after one hour