2. Cut the 240 cm long iron wire into several sections, and then weld it into a cubic frame model. What is the height of this model?
The sum of the sides of the cube is 36 cm. What is its surface area?
4. There is a cubic iron box for cookies. The bottom is square with a side length of 20 cm and a height of 30 cm. The iron box is covered with trademarks. What is the area of the trademark?
5. A cuboid reservoir is12m long, 8m wide and 4m high. If four walls and the bottom are pasted with square bricks of 4 square decimeters, how many pieces do you need?
6. Forging a cubic billet with a length of 1.2m into a rectangular steel with a cross-sectional area of 0.04m2 How long is the forged steel?
7. How many cubic meters of sand should a runway with a length of 100 m, a width of 4 m and a thickness of 8 cm be paved?
8. A 52-centimeter-long wire can be welded into a cuboid. This rectangle is 6 centimetres long and 4 centimetres wide. What is the height of this cuboid?
9. A rectangular pool is 6m long, 5m wide and1.5m high. Now the water in the pool is 36 cubic meters. What is the height of the water now?
10. Saw a piece of wood 2.4m long, 0.8m wide and 0.4m high into two cuboids. How many square meters has its surface area increased at least?
1 1, 60 cm long, 20 cm wide and 10 cm high. After putting an iron block into the water, the water level in the container just rose by 4 cm. What is the volume of this iron block?
12, ventilation duct, 2.8m long, and its cross section is a square with a side length of 2m. How many square meters of iron sheet does it take to make a 10 ventilation pipe?
13, build a brick wall with a length of16m, a thickness of 30cm and a height of 3m. If you use 540 bricks per cubic meter, how many bricks do you need for a * *?
14. After two cubes with a side length of 4 decimeters are combined into a cuboid, how many square decimeters is the surface area reduced?
15. Make a cuboid with the largest surface area with four cubes with a side length of 2 cm. What is the surface area of this cuboid?
16. A cube with a surface area of 20 square meters is cut into two identical cuboids. What is the surface area of each cuboid?
17. The surface area of a cuboid is 80 square decimeters. What is the surface area of each cube after cutting it into two identical cubes?
18, a cubic container with a side length of 2 decimeters. Pour 6 liters of water into the container. What is the water depth at this time?
19. After two identical cuboids are spliced into cuboids, the surface area is 60 square centimeters. What is the original surface area of each cube?
20. Saw a cuboid wood with a length of 1.2m into three sections, and the surface area increased by 48 square decimeters. What is the volume of primitive wood?
2 1, a cuboid with a length of 8 cm, a width of 6 cm and a height of 6 cm, can be cut into a cube with a length of 2 cm?
If the height of a cuboid is increased by 2 cm, it will become a cube. At this time, the surface area increased by 56 cm 2. What is the volume of this cuboid?
23. Cut a cuboid wood with a length of 12 decimeter, a width of 8 decimeters and a height of 6 decimeters into the largest cube. What is the volume of the cutting part?
24. Make a rectangular iron drum without a cover with 96 square decimeters of iron. It is known that the bottom of the barrel is a square with a side length of 4 decimeters. What is the volume of this bucket?
25. A cuboid with a square bottom is exactly a square with a side length of 36 cm when its four sides are unfolded. What is the volume of this rectangle?
26. The Yangtze River is 6300 kilometers long, 4700 kilometers less than the Yellow River. How many kilometers is the Yellow River?
27. Children can play games in groups of four, five or six. How many children play games?
28. A rectangular piece of paper with a length of 12 decimeter and a width of 8 decimeters should be cut into several squares with the same size.
And there is no surplus, at least how much can I cut?
Xiaoming's family bought some eggs. The number of three eggs is 1, and the number of two plus five is 1. How many eggs are there at least?
30, a group of students to participate in labor, according to their four, five, six people according to two groups, at least a few people to participate in labor.