(8.5+4.5+7)×4=80 cm
The sum of the sides of the cube is 60 cm. How many square centimeters is its surface area?
The side length of the cube is 60 ÷ 12 = 5cm.
5×5×6= 150 cm2
3. The volume of a rectangular wooden box is 672 cubic decimeters, the length of the wooden box is 12 decimeters, and the width is 7 decimeters. What is the height of this wooden box?
672 \ 12 \7 = 8 decimeters
4. A cuboid iron drum, the bottom of which is a square with a side length of 3 decimeters and a height of 7.2 decimeters. How many decimetres of iron does it take to make such a pair of uncovered buckets?
3×3+3×7.2×4= 190.8 square decimeter
5. A rectangular steel plate with a length of 24 decimeters, a width of 15 decimeter and a thickness of 0. 15 decimeter, weighing 7.8 kilograms per cubic decimeter. How much does this steel plate weigh? If the surface of steel plate is painted, how many square decimeters is the painted area?
24× 15×0. 15×7.8 = 42 1.2kg。
(24×15+24× 0.15+15× 0.15) × 2 = 731.7 square decimeter.
6. The side length of the cube is 1.5 decimeter. What is the sum of its sides? How many square decimetres is its bottom area?
1.5× 12= 18 decimeter,
1.5× 1.5=2.25 square decimeter.
7. The bottom of the cuboid tea cone is square. The side length of a square is 7 cm and the height is 1 1 cm. How many square centimeters does it take to make this tea cone?
(7× 7+7×11+7×11) × 2 = 406 square centimeters.
8. A cuboid of wood, its volume is 240 cubic decimeters. This piece of wood is 2 meters long, 6 decimeters wide and how many decimeters thick?
2 meters =20 decimeters
240/20/6 = 2 decimeters
9. Cuboid cookie jar, length and width 20cm, height 30cm. If a circle of trademark paper is attached around (not up and down), what is the area of this trademark paper at least?
20×30×4=2400 square centimeters
10. Shengli Road Primary School will dig a cuboid bunker with a length of 4.5 meters, a width of 2.4 meters and a depth of 0.5 meters.
(1) How many square meters is this bunker?
(2) How many cubic meters of sand can this bunker hold?
4.5×2.4= 10.8 m2
4.5×2.4×0.5=5.4 cubic meters
1 1. A rectangular fish tank, measured from the inside, is 60 cm long, 30 cm wide and 40 cm high, and the water level in the tank is 5 cm away from the mouth of the tank. How many milliliters of water are there in the fish tank?
60× 30× (40-5) = = 63,000 cubic centimeters = 63,000 milliliters
12. A rectangular swimming pool, 60 meters long, 25 meters wide and 2.5 meters deep.
Reinforce the walls and bottom of the swimming pool with cement. What is the area of cement?
(2) If the irrigation depth is 2m and the water weight of 1 m3 is 1 ton, how many tons of water does the swimming pool weigh?
60× 25+60× 2.5× 2+25× 2.5× 2 =1925m2
60×25×2=3000 cubic meters
3000× 1=3000 tons