For a task, Party A can do it in 10 days and Party B can do it in 15 days. The two teams can do it in X days

For a task, Party A can do it in 10 days and Party B can do it in 15 days. The two teams can do it in X days

（1/10+1/15）x=1
1/6x=1
x=1÷1/6
x=6

For a project, Party A can complete it in 15 days, Party B can complete it in 30 days, and the two teams can complete it in X days. From this condition, a project can be obtained, and Party A can complete it
For a project, Party A can complete it in 15 days, Party B can complete it in 30 days, and the two teams can complete it in X days
For a project, Party A can complete it in 15 days, Party B can complete it in 30 days, and the two teams can complete it in 3 days, and Party B can complete it in X days

1、1/15+1/30=1/x
2、3（1/15+1/30）+x/30=1