Six years later, class one students went to plant trees. If each person plants 8 trees, there will be 27 fewer trees; If there are six trees for each race, there will be five fewer trees. How many students are there in Team One? How many trees will they plant?
3。 Put 840 books on the third shelf, the number of books in the lower layer is three times that of the upper layer, and the number of books in the middle layer is twice that of the upper layer. 1. Q: How many books are there on the upper, middle and lower floors?
The number of apples bought in kindergarten is three times that of pears. After eating six apples out of 10 pears, the number of apples is still five times that of pears. How many apples and pears did you buy?
It turns out that Xiaoming's painting is three times as big as Xiaohong's, and then two people each bought five, so Xiaoming's painting is twice as big as Xiaohong's. How many photos does each of them have?
6. A bookshelf is divided into upper and lower floors, and the books on the upper floor are four times as many as those on the lower floor. After taking five books from the lower level and putting them on the upper level, there are exactly five times as many books in the upper level as in the lower level. How many books are there on the ground floor?
7. There are two baskets of oranges. If you take eight oranges from the first basket and put them in the second basket, there will be as many oranges in the two baskets. If you take 13 out of basket B and put them in basket A, the number of oranges in basket A is twice that of basket B ... How many oranges are there in baskets A and B?
1. There are x people.
5X- 17=3X-3
2X= 14
X=7
There are seven students.
2. There are X students.
8X-27=6X-5
2X=22
X= 1 1
* * * tree:11* 8-27 = 61(tree)
Or: 1 1*6-5=6 1 (tree)
Answer: There are 1 1 classmates * * There are 6 1 trees.
3. If there are X books in the upper level, the lower level books are 3X+5 and the middle level books are 2X+ 1.
X+3X+5+2X+ 1=840
6X=734
X= 139
The lower layer is: 3* 139+5=422 (Ben)
Middle layer: 2* 139+ 1=279 (Ben)
A: There are 139, 279 and 422 books on the upper, middle and lower floors respectively.
Suppose you buy x pears and 3X apples.
3X-6=5(X- 10)
3X-6=5X-50
2X=44
X=22
Apple: 3*22=66 (piece)
Apples and pears * * * are: 66+22=88 (pieces)
A: I bought 88 apples and pears.
5. Suppose Xiaohong has an X picture. Xiaoming has three photos.
3X+5=2(X+5)
3X+5=2X+ 10
X=5
Xiaoming originally had: 3*5= 15 (Zhang)
A: Xiaohong and Xiaoming originally had 5 pictures and 15 pictures respectively.
8. At the end of the term, the teacher will give an average of 35 pencils and 42 exercise books to the Miyoshi students in Class 5 (3). As a result, there were/kloc-0 pencils and two more exercise books. How many winners are there?
According to the meaning of the question, 35 pencils+1 = 36, 42-2=40 exercise books are just enough for three good students. So only the greatest common divisor of 36 and 40 is needed.
It is easy to get that the greatest common divisor of 36 and 40 is 4, so there are at most 4 winners.
9. A meadow, 30 days 17 cows, 24 days 19 cows. There are several cows. After eating for six days, four cows disappeared. How many cows are there after eating the remaining two days?
Day grass length: (17 * 30-19 * 24)/(30-24) = 9 Original grass length: 17*30-9*30=240 There are n cows, and the amount of grass eaten by cows = Original grass length+6n.
In this final math exam, the average score of female students in a class 19 is 83, and the average score of male students in class 2/kloc-0 is 88. What is the average grade of the whole class?
Solution: (83×19+21× 88) ÷ (21+19)
=( 1577+ 1848)÷40
=3425÷40
= 85.625 minutes
The school bought 40 ballpoint pens and 50 exercise books, which were awarded to the third-class students in grade four on average. As a result, there are four more ballpoint pens and two more exercise books. There are several third-class students in the fourth grade. What prize did they win?
Grade five students in a primary school 100, but less than 140. Divide them into each group 12, with 3 more people; If there are 8 people in each family, there are 3 more people. What is the number of fifth-grade students in this school?
Put 5g of salt into100g of water.
What is the percentage of salt in brine? What percentage of salt water is water?
What is the salt content in the water? How many times more water than salt?
Make a square block from a rectangular block with a length of 24cm and a width of 16cm. What is the minimum length of the side of this big square? At least this small rectangular block of wood. How many pieces?
Use square floor tiles to lay a room with a length of 24m and a width of 27m. The floor tiles to be used are all one block. What is the maximum length of floor tiles that can be used? How many tiles do you want to use?
How many square decimeters does it take to make a rectangular iron suitcase with a length of 40 cm, a width of 30 cm and a height of 20 cm? If the weight of gasoline per liter is 0.82 kg, how many kilograms of gasoline can this iron box hold?
The bridge pile is driven into the river bottom for 235m, with the water depth of1214m and the water surface of 2512m. How long is the bridge pile?
80 squares are split into a cuboid with a length of 2m, a width of 2m and a height of1.5m. What is the average volume of each square? How many cubic decimeters?
Make a bouquet with 36 red flowers and 48 white flowers. How many can I do at most?
The turnover of convenience store 65438+February 1 is 496 yuan. What is the turnover of this grocery store? 65438+February?
There are two bundles of iron wires with the same thickness, one of which is 8 meters long and weighs 400 kilograms, and the other weighs 20 kilograms. How long is this bundle of wire?
An engineering team wants to build a 4340-meter-long expressway, which has been built 1860 meters in the first six months. At this rate, how many months will it take to complete the task?
Teacher Zhang went to the store and bought 8 basketballs and 8 volleyballs. The unit price of basketball is 73 yuan, and that of volleyball is 65 yuan. How much is it more expensive to buy basketball than volleyball? (Answer in two ways)