Now the number of people is: 30*9/(9-3)=45.
To increase: 45-30= 15 people.
A clothing factory plans to produce a batch of clothes in 20 days. Due to the daily production of 10 pieces, the task was completed four days ahead of schedule. How many pieces of these clothes are there? (Use proportional solution)
Originally planned to produce X one day, now X+ 10 is produced one day.
X:(X+ 10)=(20-4):20
20X= 16(X+ 10)
X=40
That is, a * * * has 40*20=800 pieces.
3. There are three times as many literature books as science books in the library, and there are more literature books than science books 1500. How many literature books and science books are there respectively?
Science and technology books are: 1500/(3- 1)=750.
The literature book is: 750*3=2250.
4. A batch of parts shall be processed by both parties for 9 hours at the same time. It is understood that the work efficiency ratio of Party A and Party B is 3: 2. How many hours does it take for Party A to process these parts alone?
One hour * * for both parties: 1/9.
The efficiency of a is: (1/9) * 3/(3+2) =115.
That is, a single treatment time:1(115) =15 hours.
5. Master and apprentice process a batch of parts at the same time. It is known that the work efficiency ratio of mentoring is 8: 7. When the master finished processing 50% of this batch of parts, the apprentice processed 15 parts less than the master. How many parts are there in this batch?
When the master completes 50%, the apprentice completes: 50%/8*7=7/ 16.
* * * Parts:15/(50%-7/16) = 240.
6. Two typists, A and B, type a manuscript at the same time. A's work efficiency is three-fifths that of B. Two typists worked together for six days and finished two-thirds of the manuscript. How many days will it take to finish the rest?
Two people cooperate in one day: (2/3)/6= 1/9.
The efficiency of b is: (1/9)/(1+3/5) = 5/72.
The remaining B is needed separately: (1-2/3)/(5/72)=4. 8 days