A piece of square iron sheet with a side length of 30cm, subtract the square with a side length of 8cm from its four corners respectively, and then make a uncovered iron box (as shown in the figure) to calculate the volume of the iron box

A piece of square iron sheet with a side length of 30cm, subtract the square with a side length of 8cm from its four corners respectively, and then make a uncovered iron box (as shown in the figure) to calculate the volume of the iron box

(30-8 × 2) × (30-8 × 2) × 8 = 14 × 14 × 8 = 1568 (cubic centimeter) a: the volume of the iron box is 1568 cubic centimeter

A rectangular iron plate, 30 cm in length and 25 cm in width. As shown in the figure, cut the square with a side length of 5 cm from four corners, and then make a box. How many ml is the volume of this box?

Because the length of the box is 30-5 × 2 = 20 (CM), the width is 25-5 × 2 = 15 (CM), and the height is 5 cm, the volume of the box is: 20 × 15 × 5, = 300 × 5, = 1500 (CC), = 1500 (ML); a: the volume of the box is 1500 ml

There is a rectangular sheet of iron, 30 cm long and 20 cm wide. Cut a small square with a side length of 2 cm at each corner of the sheet, and then make a cuboid box without a cover. (1) calculate the volume of the box. (2) how many square centimeters of sheet iron are used to make the box?

Solution: (1) (30-2-2) × (20-2-2) × 2, = 26 × 16 × 2, = 832 (cubic centimeter); answer: the volume of this box is 832 cubic centimeter. (2) 30 × 20-2 × 2 × 4, = 600-16, = 584 (square centimeter); answer: 584 square centimeter iron sheet is used to make this box

A picture: a square iron sheet with a side length of 30 cm. Cut off a small square with a side length of 5 cm from its four corners, and then weld it into
A picture: a piece of square iron sheet with a side length of 30 cm, cut off a small square with a side length of 5 cm from its four corners, and then weld it into a uncovered slot. What is the volume of this slot?

The side length of the bottom surface is 30-5 × 2 = 20 cm
The height is five centimeters
So the volume is 20 × 20 × 5 = 2000 ml

The area of a triangle board with a bottom of 10 decimeters long and a parallelogram board with a bottom of 8 decimeters and a height of 6 decimeters is equal. How many decimeters is the height of this triangle board

Height = 8 × 6 ﹣ 1 / 2 ﹣ 10 = 9.6 decimeters

As shown in the figure, how to cut the largest circular iron sheet on a triangular iron sheet

Make the angle bisector of three angles, intersect at a point, and make a vertical line from this point to one side. Take the intersection of the angle bisector as the center of the circle and the vertical line as the radius to make a circle

There is a right triangle iron sheet (the bottom is 70cm, the height is 30cm). Master Zhang wants to take the largest square on this iron sheet, and the square area is

32.3 * 32.3 = 1043.29 square centimeter
Find a point on the 70cm side, parallel to the 30cm side, and cut the right triangle sheet into a right trapezoid and a small right triangle
Let: length of incision = x, height of right angle trapezoid = 2x
x／30＝（70－2x）／70
　　x≈16．15
Note: the combined length of small right triangle incision and right trapezoid incision is 32.3cm
Cut off the extra smaller triangles to make the largest square

A trapezoid is five sixth of a meter long at the top, one meter long at the bottom and six eleventh of a meter high. How many square meters is its area? Why take half

Area:
(5 / 6 + 1) × 6 / 11 △ 2
=1÷2
=0.5 (M2)
In the derivation of trapezoid area formula, two identical trapezoids are needed to form a parallelogram. One trapezoid area is half of the parallelogram area. Therefore, the trapezoid area should be multiplied by half (or divided by 2)

In the trapezoidal area formula s = half (a + b) h, (1) given s = 30, a = 6, H = 4, find B

Because s = 1 / 2 (a + b) H
30=1/2（6+b）×4
So B = 30 × 2 △ 4-6
=9

In the trapezoidal area formula s = half (a + b) h, S.A.B is known and H is obtained

For this kind of problem, if there is only one unknown number, then the known number can be used to represent the unknown number
Like this question:
S=（a+b)h/2
If we multiply two sides by two, we get 2S = (a + b) H
Take (a + b) as a number, divide both sides by (a + b), and H = 2S / (a + b)
The answer came out