The surface area of a 8dm long cylinder wood is reduced by 56.52dm2 after cutting a 3DM long cylinder wood along the bottom. Please calculate the remaining volume

The surface area of a 8dm long cylinder wood is reduced by 56.52dm2 after cutting a 3DM long cylinder wood along the bottom. Please calculate the remaining volume

The circumference of the bottom surface of the cylinder is: 56.52 △ 3 = 18.84 (decimeter); the radius of the bottom surface of the cylinder is: 18.84 △ 3.14 △ 2 = 6 △ 2, = 3 (decimeter); the volume of the remaining cylinder is: 3.14 × 32 × (8-3) = 28.26 × 5, = 141.3 (cubic centimeter); a: the volume of the remaining cylinder is 141.3 cubic centimeter

What is the area of the largest semicircle cut from a rectangular iron plate of 4dm in length and 3DM in width?
Fast

3 / 2 = 1.5 (DM) 3.14 * (1.5 * 1.5) = 7.065 (square decimeter) 7.065 / 2 = 3.5325 (square decimeter)

The perimeter of a rectangle is 18dm. If its length and width increase by 3DM respectively, its area will increase by () DM & # 178;

36
Let the original length be x and the width be 9-x
（x+3）（9-x+3）-x（9-x）=36

There is a square tile, perimeter is 24 decimeters, its area is how many square decimeters?

A: its area is 36 square decimeters

Cut the largest circle on a square board with a circumference of 40 cm. What is the area of this circle in square centimeters? What is the area of the remaining part in square centimeters

Side length, i.e. diameter: 40 △ 4 = 10
Radius: 5
Circle area: 3.14 × 5 × 5 = 78.5
Square area: 10 × 10 = 100
Remaining area: 100-78.5 = 21.5

Cut the largest semicircle in a 30 cm long and 10 cm wide rectangular paper. What is the area of the semicircle?

The area of this semicircle is 157 square centimeter

A square sheet of iron is 20 cm long. What's the area of the circle

Taking half of the side length of the square as the radius, we can cut out the largest circle, 20 △ 2 = 10, the largest circle area s = π R ^ 2 = 3.14 × 10 ^ 2 = 314cm ^ 2

Cut the largest semicircle in a 30 cm long and 10 cm wide rectangular paper. What is the area of the semicircle?

The area of this semicircle is 157 square centimeter

In a piece of 6 meters long, 4 meters wide rectangular sheet iron, cut out a largest circle, the circle area is () square meters
1.12.56 2.50.24 3.28.26

12.56
The largest circle is 4 meters in diameter and 2 meters in radius
3.14×2^2=12.56

Use a piece of iron wire to encircle a square with a side length of 6.28 cm. If you use this wire to encircle a circle, what is the area of the circle

Radius 6.28 × 4 △ 3.14 △ 2 = 4cm
The area of the circle is 3.14 × 4 × 4 = 50.24 square centimeter