2. A room is 6 meters long, 3.5 meters wide and 3 meters high, with 8 square meters of doors and windows. Now, the walls and top of this room should be painted with cement. What is the area of cement painting? If you need 4 kilograms of cement per square meter, how many kilograms does a * * * need?
3. The machinery factory produced 250 machine tools in early April, 150 in the middle and 200 in the late April. What percentage of the machine tools produced in April accounted for the first, middle and tenth days respectively?
1. A cuboid bunker is 4m long, 2m wide and 0.5m deep. If the yellow sand weighs 1.4 tons per cubic meter, how many tons does it weigh?
2. It is known that a rectangular tin tank with a length of 18 decimeter and a width of 10 decimeter can hold 1620 liters of water. How deep is this tank?
3. A cuboid plastic box with medicine, 0.6m long, 0.25m wide and 0.5m deep. If you put the whole box of medicine into a small bottle with a capacity of 400ml each, how many bottles should this box contain at least?
4. A cubic billet is 6 cm long and forged into rectangular steel with a cross section of 3 cm long. How many meters is steel?
5. A cuboid oil drum with a bottom area of 18 square decimeter can hold 43.2 kilograms of oil. If the weight of each liter of oil is 0.8 kg, what is the height of the oil drum?
6. In a glass jar with a length of 25cm and a width of 20cm, there is a cubic iron block with a length of10cm. At this time, the water depth is 15 cm. If this iron block is taken out of the jar, how many centimeters is the water depth in the jar?
7. A cuboid fuel tank with a square bottom and a side length of 6 decimeters measured from the inside. It contains 144 liters of oil. As we all know, the depth of the oil inside is half that of the oil tank. How many decimetres is this oil tank?
8. One room 1200 wooden floor, 40 cm long, 20 cm wide and 2 cm thick. How many square meters is this room? How many cubic meters of wood does it take to spread out this room?
9. A section of rectangular steel, with a length of1.6m and a cross section of 4cm square. It weighs only 7.8 grams per cubic centimeter. How much does this square steel weigh?
10. Make an uncovered cuboid oil drum with iron sheet. The length and width are 4 decimeters and the height is 6 decimeters. How many square decimetres is the iron sheet? Put gasoline in a barrel, and each liter of oil weighs 0.82 kg. How many kilograms of gasoline can this barrel hold?
1 1. Forge a cubic billet with a length of 0.6 meters into rectangular steel with a cross section of 0.09 square meters. How long is forged steel? (Equation solving)
12, a cuboid glass tank, measuring 40 cm long and 25 cm wide from the inside, and the water depth in the tank is 12 cm. After a stone is immersed in water, the water surface rises to 16 cm, and the volume of the stone is found.
13. Make 12 cuboid iron chimneys, each section is 2m long, 4m wide and 3m high. How many square meters of iron do you need at least?
14. The floor of Xiao Min's room is rectangular. It is 5 meters long and 3 meters wide, and has a 2 cm thick wooden floor. How many cubic meters of wood do you need at least?
15, a coal truck, viewed from the inside, is 2.5m long and1.8m wide, and the loaded coal is 0.6m high, with an average weight of1.5t per cubic meter. How many tons of coal does this truck carry?
16. rectangular iron drum without cover, with square bottom, 4m side length and 1m height. How much iron does it take to make such a barrel? How many liters of water can this barrel hold?
17. The stadium is paved with 37.5 cubic meters of cinder on a straight runway with a length of 100 meter and a width of 7.5 meters. How thick can cinder be spread?
18, rectangular children's swimming pool, 40m long,14m wide and1.2m deep. How many square bricks with an area of 16 square decimeter should be pasted on the wall and bottom of the pool now? [
19, cuboid container, bottom area 16 square decimeter, water height 6 decimeter. Now put an iron block with a volume of 24 cubic decimeters. How high is the water surface at this time?
20. Stack 2 100 cubes with a side length of 1 cm into a cuboid. Its height is 10 cm, and its length and width are greater than its height. What is the circumference of its bottom?
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