Take out 10% of the books on shelf a and put them on shelf B. the number of books on both shelves is the same. How many more books on shelf a than on shelf B?

Take out 10% of the books on shelf a and put them on shelf B. the number of books on both shelves is the same. How many more books on shelf a than on shelf B?

1－10％＝90％
90％－10％＝80％
﹙1－80％﹚÷80％＝1/4
A: the number of books in the first bookshelf is 1 / 4 more than that in the second bookshelf
To process a part, it takes 12 minutes for Party A to do it alone, 10 minutes for Party B to do it alone, and 9 minutes for Party C to do it alone. Now Party A, Party B, and Party C have made a total of 1643 parts in the same time. Q: how many parts have Party A, Party B, and Party C made?
1643 △ 112 + 110 + 19, = 1643 △ 53180, = 5580 (minutes), 5580 △ 12 = 465 (pieces), 5580 △ 10 = 558 (pieces), 5580 △ 9 = 620 (pieces), a: 465 pieces were made by a, 558 pieces by B, 620 pieces by C
The number of original books on the two bookshelves of a and B is the same. If a takes out 10 books and B takes out 18 books, then a is 1.5 times that of B. how many original books do B need fast
B: (18-10) / (1.5-1) = 16 (this)
B: 16 + 18 = 34 (original)
A, B and C process 400 parts together. It is known that it takes 10 minutes for a to process a part, 15 minutes for B, and 18 minutes for C to complete the task. How many parts are processed by each of them
A, B and C process 400 parts together. It is known that it takes 10 minutes for a, 15 minutes for B, and 18 minutes for C to process a part. How many parts do they process?
The efficiency ratio of a, B and C is 1 / 10:1 / 15:1 / 18 = 9:6:5
A processing 400 × 9 / (9 + 6 + 5) = 400 × 9 / 20 = 180
B processing 180 × 6 / 9 = 120
C processing 180 × 5 / 9 = 100
The number of books in a bookshelf is four times that in B bookshelf. If 60 books are added to B bookshelf, the number of books in two bookshelves will be the same. How many books will be stored in each bookshelf
If we regard the books on the second shelf as one, then there will be four books on the first shelf, and then there will be three more books on the first shelf than on the second shelf
According to the meaning of the title, there are 60 more books in book a than in Book B
There are books on the shelf
60 △ 4-1 = 20
A there are books on the shelf
20 × 4 = 80
If there are x books on shelf B, then there are 4x books on shelf A. according to the meaning of the title: 4x = x + 60 x = 20, there are 80 books on shelf a and 20 books on shelf B
If we regard the books on the second shelf as one, then there will be four books on the first shelf, and then there will be three more books on the first shelf than on the second shelf
There are more than 60 inscriptions in B than in a
There are books on the shelf
60 △ 4-1 = 20
A there are books on the shelf
20 × 4 = 80
If there are x books on shelf B, there are 4x books on shelf a
x+60=4x
4x-x=60
3x=60
x=20
4x=4×20=80
A: there is... Unfolding on the bookshelf a
If we regard the books on the second shelf as one, then there will be four books on the first shelf, and then there will be three more books on the first shelf than on the second shelf
According to the meaning of the title, there are 60 more books in book a than in Book B
There are books on the shelf
60 △ 4-1 = 20
A there are books on the shelf
20 × 4 = 80
If there are x books on shelf B, there are 4x books on shelf a
x+60=4x
4x-x=60
3x=60
x=20
4x=4×20=80
A: there are 80 on shelf a and 20 on shelf B. Put it away
The three workers of a, B and C made 795 parts at the same time. It took six minutes for a, five minutes for B and four minutes for C to make a part
6 / 1 minute to make a part
We can make 1 / 5 parts in one minute
C 1 / 4.5 parts per minute
The number of parts manufactured in one minute is 1 / 6 + 1 / 5 + 1 / 4.5 = 53 / 90
The total time for three persons: 795 (53 / 90 / min) = 1350 minutes = 22.5 hours
Among them,
A: 1350 minutes △ 6 minutes / piece = 225 pieces
B: 1350 minutes △ 5 minutes / piece = 270 pieces
C: 1350 minutes △ 4.5 minutes / piece = 300 pieces
There are two barrels of oil with a mass ratio of 7:3. If 12kg is taken from the big barrel and poured into the small barrel, the oil in the two barrels is exactly the same. How much oil is there in the two barrels?
12 × 2 △ 7-3 = 24 △ 4 = 6 (kg) 6 × 7 = 42 (kg) 6 × 3 = 18 (kg) a: there was 42 kg oil in barrel a and 18 kg oil in barrel B
Party A and Party B process 9 parts in 10 minutes and Party B 14 parts in 15 minutes. How long does it take to make one part on average? Who is more efficient?
The time of a is 10 | 9, and that of B is 15 | 14, so the efficiency of B is high
A and B have two bookshelves. It is known that a bookshelf has three times as many books as B. If a bookshelf has 80 more books and B has 100 more books, a is twice as much as B
Q: how many books are there on shelf B?
Suppose that bookshelf B has x books, then bookshelf a has 3x books, (3x + 80) = 2 (x + 100), x = 120,
Therefore, there were 120 books on shelf B
Are you sure there is no mistake in this problem? I'm negative. I'm not.
The two workers, a and B, worked together to process a batch of machine parts and completed the task in 20 days. It is known that a makes three more parts a day than B, and B asks for five days' leave in the middle of the day, and the number of parts completed by B is exactly half of that of A. how many parts are there in this batch?
The number of parts completed by Party B is exactly half of that of Party A. then: Party B completes 13% of the total workload, and Party A completes 23% of the total workload; Party A's work efficiency: 23 △ 20 = 130; Party B's work efficiency: 13 △ 20-5, = 13 △ 15, = 145; 3 △ 130-145, = 3 △ 190, = 270; answer: the total number of parts is 270