![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
Three equal size squares, put together into a rectangle, the circumference of this rectangle is 24 cm, the side length of each square is 24 cm______ Centimeter. What's the area of this rectangle______ Square centimeter
24 △ 8 = 3 (CM), 3 × 3 × 3 = 27 (cm 2)
The circumference of a rectangle is 36 cm. If the length is reduced by 4 cm and the width is increased by 2 cm, the rectangle will become a square
Then how many equations are the side length of the square
Let the length of a rectangle be x and the width be y
Then 2 * (x + y) = 18; x-4 = y + 2
The solution is: x = 12; y = 6
Then the square side length = x-4 = y + 2 = 8
The square cardboard with side length of 30cm is cut and folded into a cuboid box. It is known that the width of the cuboid is twice the height and the length is twice the width
Find his volume
Is the width twice the height and the length twice the width?
If the height is xcm, the width is 2xcm and the length is 4xcm
Surface area = 30 × 30 = 90 (CM & # 178;)
（x×2x+x×4x+2x×4x）×2=900
2（2x²+4x²+8x²）=900
x²=900/28
x=(15/7)√7cm
Volume = 4x × 2x × x = 8x & # 179; = 8 × (900 / 28) × (15 / 7) √ 7 = (27000 / 49) √ 7 (CM & # 179;)
The square cardboard with a length of 40 cm on one side is cut properly and folded into a rectangular box (the thickness of the cardboard is ignored) (1) As shown in the figure, if you cut a square of the same size at each corner of the square cardboard, and fold the rest into a rectangular box without cover. ① to make the bottom area of the folded rectangular box 484cm2, what is the side length of the cut square? ② Is there a maximum side area of the folded rectangular box? If there is, find out the maximum value and the side length of the square cut off at this time; if not, explain the reason. (2) if some rectangles are cut off around the square cardboard (that is, at least one edge of the cut rectangle is on the side of the square cardboard), fold the remaining part into a rectangular box with a cover. If the surface area of a rectangular box is 550cm2, find out At this time, the length, width and height of the rectangular box (only one case meeting the requirements is required)
(1) Let (40-2x) 2 = 484, that is, 40-2x = ± 22, the solution is X1 = 31, X2 = 9, and the side length of the cut square is 9cm. ② there is a maximum side area. Let the side length of the cut square be ACM, and the side area of the box be ycm2, then the functional relationship between Y and a is y = 4 (40-2a) a, that is, y = - 8a2 + 160A, that is, y = - 8 (a) -10) 2 + 800, when a = 10, y max = 800. That is, when the side length of the cut square is 10cm, the maximum side area of the rectangular box is 800cm2. (2) in a kind of cutting diagram as shown in the figure, let the height of the cut rectangular box be TCM. 2 (40-2t) (20-t) + 2x (20-t) + 2x (40-2t) = 550, and the solution is: T1 = - 35 (out of the question, rounding), T2 = 15 40-2 × 15 = 10 (CM), 20-15 = 5 (CM), and the cuboid box is 10 cm long, 5 cm wide and 15 cm high
Mathematics test question: the side of the square cardboard 40 cm long, appropriate cutting, folded into a rectangular box (cardboard)
23. Cut the square cardboard 40 cm long on one side and fold it into a rectangular box (the thickness of the cardboard is ignored)
(1) As shown in the picture, if you cut a square of the same size at the four corners of the square cardboard, fold the rest into a rectangular box without cover
① To make the bottom area of the folded rectangular box 484cm2, what is the side length of the cut square?
② Is there a maximum value of the side area of the folded rectangular box? If so, find out the maximum value and the side length of the square cut off at this time; if not, explain the reason
(2) If you cut off some rectangles around the square cardboard (that is, at least one edge of the cut rectangle is on the edge of the square cardboard), fold the remaining part into a rectangular box with a cover. If the surface area of a rectangular box is 550cm2, calculate the length, width and height of the rectangular box (only one case that meets the requirements is required)
Why can't the answer be 20 in length and 2.5 in width,
(1) (1) the side length of the bottom surface √ 484 = 22, so that the cut part (40-22) / 2 = 9cm; (2) if the cut side length is x, then the side area is & nbsp; 4 * x * (40-2x) when x = 10, take the maximum value of 800, so that the maximum side area is 800cm ^ 2 when the cut side length is 10cm; (2) the cut method with cover is shown in the figure, and the square is not well drawn
A 18 cm long, 4 cm wide rectangular cardboard, you can cut () side length of 2 cm small square
A. 9 B. 18 C. 36
A: you can cut out 18 small squares with a side length of 2 cm
A box without a cover can be made by subtracting the four corners of a 24 cm long rectangular cardboard from a small square with a side length of 3 cm. The volume of the box is known to be 486 cubic centimeters. How many square centimeters is the area of the original rectangular cardboard?
Let the width of the original rectangle be xcm
3*（x-3*2)*(24-3*2)=486
The solution is x = 15
The original area of rectangular paperboard is: 24 * 15 = 360 (square centimeter)
Answer: the area of original rectangular paperboard is 360 square centimeter
A piece of paper is 24cm in length and 18cm in width. If it is cut into several square pieces of paper of the same size and there is no surplus, what is the maximum area of the square piece of paper?
A piece of paper is 24cm in length and 18cm in width. If it is cut into several square pieces of paper of the same size without any surplus, what is the maximum area of square pieces of paper?
The side length of such a square is the greatest common divisor of the length and width of a rectangle
The greatest common divisor of ∵ 24,18 is 6
The side length of the square is 6 cm
The square area is 36 cm & sup2;
A piece of rectangular paper, 24cm long and 18cm wide, should be divided into several small squares. What is the maximum side length of a small square
It takes an hour to burn an uneven rope. How to use it to judge half an hour
3. Suppose there is a pond with infinite water in it. Now there are two empty water pots with the volume of 5 liters and 6 liters respectively. The problem is how to get 3 liters of water from the pond with two water pots
4. There are 10 parts with the same appearance, one of them is defective, and the quality is lighter than the other 9 parts,
Science: in the 2nd century A.D., Ptolemy of Greece established the theory of the geocentric universe, which he mistakenly believed (what)
2. Polish astronomer () wrote the great book on the motion of celestial bodies and founded ()
3. Foucault proved ()
A rectangular paper, 24cm long and 18cm wide, should be divided into 12 small squares. The maximum side length of a small square is 6
It takes half an hour to finish burning
3. Pour 6 liters of water from a 6-liter kettle into a 5-liter kettle, and there are 2 liters left in the 6-liter kettle. Pour 2 liters of water into a 6-liter kettle, and there are 6 liters left in the 5-liter kettle, and there are 1 liter left in the 6-liter kettle. Pour 1 liter left in the 5-liter kettle, and there are 3 liters left in the 6-liter kettle
The first time: 5 for each of the two, and there are defective products in the light 5
The second time: the defective products are divided into three groups: 2, 2 and 1. If the weight of 2 and 2 is the same, one is the defective product
If it's not the same weight, separate and weigh the lighter group
To sum up, at least three times can guarantee to find out the defective products
Science: in the 2nd century A.D., Ptolemy of Greece established the theory of the center of the universe
2. Polish astronomer (COPERNICUS) wrote the great book "on the movement of celestial bodies" and founded (heliocentric theory)
3. Foucault proved (the rotation of the earth) by experiment
Lay a square with a rectangular floor tile of 24cm in length and 18cm in width (all the floor tiles are used as a whole). How long is the side length of the square at least?
My way is equal to 72 (absolute), but how?
This problem is to find the least common multiple of 24 and 18
The least common multiple of 24 and 18 is 72
So the side length is at least 72 cm
Sure
Qiufeng Yanyan answers for you
What do not understand can continue to ask, online at any time, etc
If my answer is helpful to you, please select it as a satisfactory answer in time. Thank you~~
RELATED INFORMATIONS
- 1. How many pieces of rectangular iron pieces, 90cm long and 42cm wide, should be cut into square iron pieces with the same area and the same number of centimeters, if there is no surplus?
- 2. You want to cut the rectangular paper of 84 cm in length and 72 cm in width into a square paper of the same size to make a lantern. What is the maximum side length of this square paper without any remaining
- 3. 1. The surface area of a cube is 8.64 square decimeters, and the area of a surface is () 2. Weld a 36 cm long iron wire into a cube frame. Its edge length is () cm 3. The area of one side of a cube is 25 square centimeters, and the sum of its edges is () centimeters 4. A 48 cm long iron wire can be welded into a cuboid of 5 cm long, 4 cm wide and () cm high 5. After a cuboid block is cut into two pieces, the surface area increases by 12 square centimeters. What is the surface area of this cuboid?
- 4. The bottom area of a cube is 25 square decimeters, its surface area is (square decimeters), and its volume is () cubic meters
- 5. The bottom area of a cube is 25 square meters, so its surface area is () square meters, and its volume is () cubic meters
- 6. Use a 24 decimeter iron wire to weld the largest cube frame. What is the surface area and volume of the cube
- 7. A 84 decimeter long iron wire is made into a cube frame. The surface area of the cube is () square decimeter, and the volume is () cubic decimeter fast
- 8. A 48CM long iron wire is welded into a cube frame (the joint is ignored). The surface area of the cube is () square centimeter and the volume is () cubic centimeter
- 9. A 48 cm long wire is welded into a cube frame. What is the volume of this frame? Analytical formulation
- 10. A 24 cm long iron wire is welded into the largest cube model. What is the surface area and volume?
- 11. A rectangular cardboard, 1.6 decimeters long, 8 cm wide, cut diameter is 4 cm circle, how many can cut at most?
- 12. Draw a quadrilateral with only one axis of symmetry, and then draw a quadrilateral with only two axes of symmetry
- 13. Choice: a rectangle is 12 cm long and 8 cm wide. If you cut a square with 2 cm side length around it, the perimeter of the figure will be left A. Decrease 16cm B, unchanged C, increase 16cm
- 14. There is a 24 cm long, 18 cm wide rectangular iron sheet, which is welded into a box without a cover by subtracting the square with a side length of 4 cm from the four corners, What's the surface area of this box
- 15. You need at least () cm long wire to make a cuboid frame with a perimeter of 18 cm at the bottom and a height of 5 cm
- 16. Make a cuboid oil tank without cover with iron sheet. The bottom is a square with side length of 2 decimeters and the height is 1.5 meters. How much iron sheet do you need to make such an oil tank?
- 17. A rectangular piece of paper is 60 cm long. After cutting off the largest square, a small rectangle is left. What is the perimeter of this small rectangle?
- 18. A cuboid is 26 cm high. It is cut into two cuboids horizontally. The surface area is increased by 80 square cm
- 19. A rectangular sheet of iron, 26 cm in length and 16 cm in width, is cut off from its four corners. The square with a side length of 3 cm is then welded into an open iron box. How many ml is the volume of this iron box?
- 20. A coin with a radius of 1cm rolls along the edge of the triangle cardboard. The three sides of the triangle are 6cm, 7cm and 8cm respectively. When the coin rolls back to its original position, what is the distance of the center of the coin