1, a batch of parts, originally planned to be distributed to mentoring for processing at 8: 05. The master actually processed 1600 pieces, which exceeded 25% of the assigned tasks, while the apprentice only completed 6% of the tasks. How many pieces did the apprentice actually process?

Master's task:1600 ÷ (1+25%) =1280 (pieces)

Apprenticeship task: 1280÷8x5=800 (pieces)

Actual processing of apprentices: 800X6%=48 (pieces)

2. Workshop A, Workshop B and Workshop C process a batch of parts at the same time. Workshop A accounts for 40% of the total number of parts processed, and the ratio of the number of parts processed in Workshop B and Workshop C is 7: 5. Workshop A processes 240 more parts than Workshop C. How many parts are there in this batch?

Processing in Workshop B and Workshop C: 1-40%=60%

Workshop C treatment: 60%x5/(7+5)=25%

Workshop A processes more than Workshop C: 40%-25%= 15%.

Workshop a processes 240 more parts than workshop C.

The composition of this batch of parts is: 240÷ 15%= 1600 (pieces).

3. The ratio of the number of the two engineering teams is 7: 3. If 20 people are sent from Team A to Team B, the ratio is 3: 2. How many people are there in the two engineering teams?

The total number remains the same:

A: B =7:3.

A: B =3:2=6:4。

Each serving: 20(7-6)= 20 (person)

The two construction teams of Party A and Party B originally had:

20x(7+3)=200 (person)

There are 960 science and technology books and literature books in the library, and their ratio is 8: 7. Later I bought some literature books. At this time, the ratio of literature books to science and technology books is 15: 16. How many literary books did you buy?

The number of scientific and technological books remains the same:

Science and technology books: literature and art books =8:7= 16: 14.

Science and technology books: literature and art books = 16: 15.

Each copy: 960( 16+ 14)= 32 (copies)

I also bought a literature book: 32X( 15- 14)=32 (this book).