1, for a project, Party A needs to do it alone 15 days, and Party B needs to do it alone 12 days. Now that Party A and Party B have cooperated for three days, Party A has other tasks, and the rest of the project will be completed by Party B alone. How many days does it take to complete all the projects?

2. The pool has a water inlet pipe and a drainage pipe. If the water inlet pipe is opened separately, the pool can be filled in 6 hours; If the drain pipe is opened separately, the water can be discharged in 8 hours; If the water inlet pipe and the water outlet pipe are opened at the same time, how many hours can you fill with water? If the water inlet pipe is opened first, and the water inlet pipe and the drainage pipe are opened at the same time, how many hours will it take to fill with water?

3. A pool is equipped with three water pipes, A, B and C. A and B are water inlet pipes and C is drainage pipe. It takes 6 hours for A to fill a pool of water, 8 hours for B to fill a pool of water, and 24 hours for C to fill a pool of water. Now, how many hours can a pool of water be filled with three pipes?

4. To process 200 parts, Party A will work alone for 5 hours, and then cooperate with Party B for 4 hours to complete the task. It is known that Party A processes 2 more parts per hour than Party B. How many parts do Party A and Party B process per hour?

5. It takes 65,438+00 days, 65,438+02 days and 65,438+05 days for Party A, Party B and Party C to complete a project alone. Now it is calculated that the project will be completed in 7 days, and Party B and Party C will work together for 3 days. Team b should leave and be replaced by party a. Can the project be completed as planned without changing the work efficiency of each team?

In order to celebrate the opening of the school sports meeting, the students in Class Two, Grade One accepted the task of making a small national flag. Initially, half of the students planned to make 40 noodles every day. After completing 1/3, the whole class will join in. As a result, the task was completed one and a half days ahead of schedule. Assuming everyone's production efficiency is the same, how many small flags did * * make?

answer

1, [1-(1of15, 12 1)×3] 1+312 =/kloc.

2.1÷ (/kloc-0 in 6/65438 in-8+0) = 24 hours.

(1-61× 2) ÷ (1-81)+2 =18 hours.

3.1÷ (65438 in 6+0+81-65438 in 24+0) = 4 hours.

4. Solution: If Party A processes X parts per hour, then Party B processes (x-2) parts per hour.

(x+x-2)×4+5x=200。

The solution is x= 16.

So A processes 16 parts per hour, while B processes 14 parts per hour.

5, [1-( 1 of 12, 1 of 05)×3]÷ 10, 1 of 15.

This project can be completed as planned.