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A rectangular food box is 8 cm long, 6 cm wide and 10 cm high. If a circle of brand paper is pasted around the food box, how many square meters is the area of the brand paper at least?
(8 × 10 + 6 × 10) × 2 = (80 + 60) × 2 = 140 × 2 = 280 (square centimeter); 280 square centimeter = 0.028 square meter
A rectangular iron food box, 12 cm long, 8 cm wide and 15 cm high. If a circle of brand paper is pasted along its side, what is the area of this brand paper
How many?
12×15×2+8×15×2
=360+240
=600 (square centimeter)
A circle of label paper is pasted around a rectangular food box with a length of 1 decimeter, a width of 8 cm and a width of 5 decimeters
The area of this brand paper is at least ()
This problem is equivalent to finding its surface area
①1dm=10cm
②1.5dm=15cm
③（10×5+8×5）×2=180cm²
④180+100=280cm²
Hope to adopt it~
Three fifths of a square meter equals () square centimeter
1㎡=10000c㎡
Three fifths square meter = 0.6x10000 = 6000 square centimeter
Nanjing Yangtze River Bridge, the lower railway bridge is 6772 meters long, of which the main river bridge is 1577 meters long. It took two minutes for a 300 meter long train to pass through the main river bridge? (2) How long does it take to cross the whole railway bridge at this speed?
As shown in the figure, in square ABCD, ab = 2, e and F are on BC and CD respectively, and CE = cf. if the area of triangle AEF is 1, find the length of EF
Let CE length be a, then the area of triangle AEF = 2 * 2-1 / 2 * 2 * (2-A) - 1 / 2 * 2 * (2-A) - 1 / 2 * A & # 178; = 1
That is a & # 178; - 4A + 2 = 0, the solution is a = 2 - √ 2
So EF = √ 2A = 2 (√ 2-1)
The speed of light propagation in vacuum is 3.0 X10 to the eighth power meters per second. How many kilometers is 1 light year (365 days) (the distance of light propagation in a year) equivalent to?
Please advise!
365 * 24 * 60 * 60 * 3 * 10 ^ 8 = 9460 billion km
A mobile communication company carries out two kinds of services: the users of "global" pay 50 yuan monthly rent, and then pay 0
A mobile communication company carries out two kinds of services: "global" users pay 50 yuan monthly rent, and then pay 0.4 yuan for each minute of the call; "Shenzhouxing" does not pay the monthly rent, and pays 0.6 yuan for each minute of the call
(1) How much is the cost of the two methods expressed in algebraic form?
(2) For a certain call time, will the two modes cost the same amount?
3) If someone estimates that they can talk for 300 minutes in a month, which way is more cost-effective?
(1) Assuming that the cost of global communication is Y1 and the cost of China travel is Y2, we get the following results:
Y1=50+0.4X
Y2=0.6X
(2) Let Y1 = Y2, that is, 50 + 0.4x = 0.6x
It is calculated that x = 250, that is, the cost of the two methods is equal when the call is 250 minutes
(3) Substituting x = 300 into the two equations, Y1 = 50 + 0.4 * 300 = 170 can be obtained
Y2=0.6*300=180
So Y1
In diamond ABCD, AC = 8cm, BD = 6cm, then the area of diamond is______ ．
∵ AC = 8cm, BD = 6cm, the area of rhombus = 12ac · BD = 12 × 8 × 6 = 24cm2
Solving equation x square + 6x-360 = 0
X square + 6x-360 = 0
x²+6x+9=369
(x+3)²=369
∴ x+3=±3√41
Ψ x = - 3 + √ 41 or x = - 3 - √ 41
RELATED INFORMATIONS
- 1. A cuboid food box is 10 cm long, 8 cm wide and 12 cm high. Stick a circle of brand paper around it. How many square centimeters should the area of brand paper be at least?
- 2. In a cylindrical bottle with a bottom radius of 10 cm, the water depth is 8 cm. To put a piece of iron in the bottle, which is 8 cm in length and 15 cm in width and 15 cm in height, how many cm does the water surface rise when the iron is placed vertically in the water?
- 3. In a cylindrical bottle with a bottom radius of 10 cm, the water depth is 8 cm. To put a piece of iron in the bottle, which is 8 cm in length and 15 cm in width and 15 cm in height, how many cm does the water surface rise when the iron is placed vertically in the water?
- 4. In a cylindrical glass tank with a bottom radius of 10 cm and a water depth of 8 cm, an iron block of 8 cm in length and width and 15 cm in height should be placed in the tank 1. How many centimeters will the water surface rise when the iron block is placed horizontally in the water? 2. Put the iron block in the water vertically, how many centimeters will the water rise?
- 5. A cube lead block with an edge length of 8 cm is installed in a cuboid glass tank of 16 cm long, 10 cm wide and 20 cm high, and then some water is put into the tank to completely submerge the cube lead block. When the lead block is taken out of the tank, how many cm will the water in the tank drop?
- 6. A cuboid is 8 cm in height, 1 / 2 in width and 5 / 4 in width. The cuboid is () cm in width, () cm in length, () cm in edge length, () m3 in volume and () cm2 in surface area
- 7. The circumference of the bottom of a cuboid is 36 cm, and the height is 8 cm. What is the total length of the edges of the cuboid?
- 8. The circumference of the bottom of the cuboid is 36 cm and the height is 8 cm. The total length of the edges of the cuboid is () cm
- 9. Use three cuboids that are 3cm long, 2cm wide and 1cm high to form a large cuboid with the smallest surface area. How many square centimeters is the surface area of this cuboid
- 10. There is an empty cuboid container a 40 cm long, 30 cm wide and 20 cm high. There is another cuboid container B 30 cm long, 20 cm wide and 24 cm deep. Now pour part of B's total water to a so that the water in the two containers is the same height. How many cm deep is the container
- 11. Cut a cuboid 16 cm long, 8 cm wide and 10 cm high into two cuboids of exactly the same shape and size. What is the maximum and minimum surface area of the cuboid?
- 12. Cut a cube with an edge length of 8 cm into two cuboids of the same shape and size. The volume () and surface area () of each cuboid
- 13. A rectangle shaped plexiglass is 10 cm long, 8 cm wide and 6 cm high. Cut the largest cube on the plexiglass and find the rest
- 14. A cuboid glass jar is 4 decimeters long, 3 decimeters wide and 5 decimeters high. After pouring water, the water depth is 3.5 decimeters, and the poured water is () liters A. 60B. 42C. 52.5
- 15. Pour 18 liters of water into a rectangular glass tank 4 decimeters long, 3 decimeters wide and 2 decimeters high. How many decimeters is the distance between the water surface and the tank mouth?
- 16. There is water in a sealed rectangular glass fiber reinforced plastic. The lengths of the three edges intersecting one vertex of the glass jar are 10 cm, 6 cm and 5 cm respectively. Put the glass jar on the water surface in three different ways. The minimum height of water is 2 cm. What is the maximum height of water? (please draw a sketch and calculate it.)
- 17. In a 6-decimeter-long, 4-decimeter-wide and 3-decimeter-high rectangular glass jar, the water depth is 2 decimeters, The water depth becomes 2. Find the volume of the iron ball
- 18. A 40 cm long, 20 cm wide and 30 cm high cuboid glass jar is 18 cm deep. Now an iron ball is completely immersed in the water, and the water surface rises to 25%
- 19. As shown in Figure 1, the water depth in a closed rectangular glass tank is 3 cm. If the glass tank is placed as shown in Figure 2, how many cm is the water depth inside?
- 20. When a rectangular iron block with a bottom area of 4 square centimeter is put into a glass container with a bottom area of 20 square centimeter, the water in the container rises by 1 centimeter Ask for the height of the iron