Elementary School Math Application Questions! There is a heavy reward .

Solution: The number of science and technology books is:

4) Let the science book be x, then x 11 20-84=400 further solve x and get the equation as:

5) Let the science book x, then 400 3 4=x 60% further solve x and get the equation as:

6) Let the science book be x, then (x+400) 60% = 400 further solution x is calculated as:

Science and technology books are x books.

1.Four-fifths * x = 400

5/6 = x

4.Eleven tenths * x-84 = 400

5.Three-quarters * 400 = 60% * x

1. Science and technology book = 400 (4 5).

2. Science and technology book = 400 * (1 + 1 5).

3. Science and technology book = 400 (8 5).

4. Science and technology book = (400 + 84) (11 20).

If the annual production is 6800, then the annual production is 62800 + 6800 = 69600.

42,900 units were produced in the first half of the year, then 69,600-42,900 = 26,700 units should be produced in the second half of the year.

An express train and a slow train traveled from A and B at the same time, and after 3 to 5 hours, they met at a distance of 3 km from CLP. It is known that the fast train has a star of 75 kilometers per hour, and the slow train has a star of how many kilometers per hour?

Solution: Meeting at a distance of 3 km from the midpoint means that the fast train travels 3 2 = 6 km longer than the slow train, assuming that the slow train has a speed of x km.

75×3/5-3/5x=6

45-3/5x=6

x=65 I'm a teacher, thank you for adopting.

Solution: 75 times 3 5 = 45 (km).

45-3 times 2 = 39 (km).

39 divided by 3 5 = 65 (km-h).

A: Slow trains travel 65 kilometers per hour.

The express train traveled in total: 75 * (2 3) = 45 (km).

Whole: (45-3)*2=84 (km).

Slow speed: 84 (2 3)-75=65 (km/h).

person) 50 50% = 25 (person).

50 2 5 = 20 (person).

25 + 20-7 = 38 (people).

50-38=12 (people) A: 50 volunteers, 12 people clean windowsSet a total of x baskets of melons.

x-(50%x+50%x·3 5)=1 5x Answer: 1 560%-40%=20%=400 (pages) Answer: 400 pages 115%-100%=15%.

12 15% = 80 (person).

80 3 4 = 60 (person).

80 40%=32 (person) Answer: 60 students in the mathematics group and 32 people in the language group 5There are 3 of them, one of each type.

6.Solution: Let this number be x.

1/2x=25%x+10

x =40 Answer: This number is 40

7.(180-9 5 45) 9 5=55 (kmh) Answer: 55 km/h.

Meta) - bookshelves.

250-100 = 150 (yuan) - bed.

page) kg) yuan) deposit for a three-year period.

12.[24 (1-88%)] 88% = 176 (person) grams).

person) 2 11 = 22 (person).

2 10 = 20 (person).

kg) 5 4 = 20 (kg).

1, 7 14% = 50--- total number of people.

50 (number of people cleaning windows.)

Total number of students 80 3 4 = 60 --- number of mathematics.

80 40% = 32 --- number of languages.

5 3 pcs. 6 Let this number be x

1/2x-25%x=10

Solution x=20

7: (180-45 9 5) 9 5=558: A bookshelf is 100 yuan more expensive than a bed, and the ** of the bed is three-fifths of the bookshelves. How much do bookshelves and beds cost?

100 (1-3 5) = 250 – bookshelves.

250 3 5 = 150 - bed.

11: Three-year deposit method 5000 5% 3=750 one year plus two years deposit method 5000

One-year deposit method 5000 5000+5000 So the three-year period is appropriate.

The question is very simple, the score is too low, plus 80 points to someone to help you do it!

Make one for you first, add 80 points and then give the others : total number = 7 (person;

The number of people sweeping the corridor = 50 * people;

Number of garbage transporters = 50 * (2 5) = 20 people;

Number of people cleaning windows = 50-25-20 + 7 = 12 people.

1. The total number of volunteers: 7 14%=50 (people) The number of people who clean windows: 50 (1-50%-2 5+14%) = 12 (people).

2. A fraction of this basket of bananas remains: 1-50%-50% 3 5=1 5

3. There are 80 [60%-(1-60%)] = 400 (pages) in this book

4. Number of participants in the language group: 12 (3 4+40%-1) 40%=32 (people).

Number of participants in the mathematics group: 12 (3 4+40%-1) 3 4=60 (people).

5. A: There are 3 balls in total. One red, one yellow, and one green ball.

6. This number is: 10 (1 2-25%)=40

7. The total number of kilometers traveled by car B: 180 9 5-45 = 55 (kilometers).

8. The amount of money on the bookshelf: 100 (1-3 5) = 250 (yuan); The amount of money for the bed: 250 3 5 = 150 (yuan).

9. The number of pages of the book: 16 (3 5-1 3) = 60 (pages).

10. The number of kilograms of this batch of fruits: 24 (1 3-1 4) = 288 (kg).

11. Answer: The interest you get for three years is more, is: 5000 5% 3=750 (yuan).

The interest rate for one year is about: 543 yuan; The interest on a fixed deposit for two years and a fixed term for one year is about 630 yuan. (Process omitted).

12. The number of people who passed the foreign language test is: 24 (1-88%) 88%=176 (people).

13. The water to be evaporated is: 200-200 10% 16% = 75 (grams).

14. Number of boys: 2 10 (11-10)=20 (people); Number of girls: 2 11 (11-10) = 22 (person).

15. It turns out that there is fruit in the first basket: (5+5) (1-3 4)=40 (kg).

16. The ratio of students in the fifth and sixth grades is: 13

17. The total length of this boulevard: 15 (1 2-3 10) = 75 (km).

18. The time for the completion of the cooperation between the two workshops is: 1 (1 4 + 1 6) = hours).

19. The meeting time is: 1 (1 3 + 1 5) = hour).

20. Analysis: There are no more than 50 students in this class, and the number of students in the class is a multiple; That is, the class size is 40 people.

The number of people who have not read a single masterpiece is the number of students in the class (1-1, 2). i.e. 40 (1-1 2) = 20 (person).

1.7 14% = 50 (person).

22 (person) Answer: There are 22 people in total. There were 22 people cleaning glass.

A: 20% left.

3.Solution: There are a total of x pages.

60%x-（1-60%x）=80

20%x=80

x=400A: There are 400 pages in total.

1. If there are x volunteers, then 14%x=7, x=50

There are 50x1 2=25 people who sweep the stairway, and 50x2 5=20 people who carry garbage.

Because there are 7 people doing these two things, there are 50-(25+20-7)=12 people who wipe the glass.

2, the first time sold 1 2, the second time sold the first 3 5, that is, sold 1 2x3 5 = 3 10

Then there is 1-1 2-3 10=1 5 left in this box

3. If the book has x pages, then 60 100x-40 100x=80, and the solution is x=400

4. If there are x people, then 3 4x+2 5x-x=3 20x, 3 20x=12, x=80, so the math group has 80x3 4=60, and the language group has 80x2 5=32

5, there are 3 balls in total.

6. Let this number be x, then 1 2x-25%x=10, x=40

7, A walked a total of 9 5x45 = 81 km, then B walked 180-81 = 99 km, 99 divided by 9 5 = 55 km, so B walked 55 km per hour.

8. If the bookcase is x, the bed is 3 5x, x-3 5x = 100, then x = 250, so the bookshelf is 250 yuan, and the bed is 150 yuan.

9. If the book has x pages, then 1 3x+16=3 5x, x=64

10, set a total of x kilograms, 1 3x-1 4x = 24, x = 288, a total of 288 kilograms.

Do so much first, and I'll give you the answer later.

Total number = 7 (person;

The number of people sweeping the corridor = 50 * people;

Number of garbage transporters = 50 * (2 5) = 20 people;

Number of people cleaning windows = 50-25-20 + 7 = 12 people.

The real perseverance in answering the questions...