A rectangular piece of paper, 5 28 decimeters long and four decimeters wide, encloses them with two

A rectangular sheet of paper is 4dm long and 4dm. wideUse it to enclose two cylinders, and they are the same size.

Decimeter to do the bottom circumference:

Bottom radius: decimeter, bottom area: square decimeter, v = cubic decimeter, 4 decimeter as the bottom perimeter:

Bottom radius: 4 (2 dm, bottom area: square decimeter, v = cubic decimeter, volume is not the same, volume difference: cubic decimeter.

It's definitely not the same, it's a double difference.

1) Surround the cylinder with a height of 4 decimeters. The circumference of the base is and its radius is about.

The volume is 2) to be high and enclosed into a cylinder. The circumference of the underside is.

4dm, which has a radius of .

The dm volume is.

Obviously, the two are not equal in size.

Summary. Because the ratio of length to width is 3:2, the width is the side area, which is the area of this rectangular paper, so it is the length multiplied by the width.

1.A rectangular piece of paper, centimeters long, the ratio of length to width is 3:2 with this rectangular paper to enclose a cylinder, this.

Please complete the question.

Isn't it a centimeter in circumference??

Roger that. The side area is. Formula.

Thank you. Wait a minute.

I think it's also long.

The side area is a square centimeter. Formula.

Because the length is, the ratio of length to width is 3:2, so the width is the side area, which is the area of the base of this rectangular paper, so it is the long leather front chop multiplied by the width.

Thank. The footprint is:

This problem is to find the area of the circle.

The circumference of the base surface can be found from the side area and height.

Once you find the perimeter, you can find the radius, and knowing the radius you can find the area.

Thank you. I think I can understand how to solve the problem.

Source circumference of the bottom area of the cylinder: 2 r=50

Radius of the bottom area of the cylinder: r=50 cm.

Bottom area of the cylinder: r = square centimeter.

Cylinder volume = base area * height: cubic centimeters such as cracks.

Enclose a rectangular piece of paper 5 cm long and 4 cm wide into a cylinder, with (4) cm as the height and volume of cubic centimeters.

The maximum volume is (5 2) 4 = 25 cubic centimeters.

Solution: It is known that a rectangular paper with a length of decimeters and a width of 2 decimeters is used to enclose a cylindrical paper tube, and the side area of the paper tube = the area of the rectangular paper is obtained.

Length and width. = 9 square decimeters.

A: Its side area is 9 square decimeters.

The side area is 9 square decimeters.

It is different to use the length of the rectangle to make the circumference of the bottom surface of the cylinder, and the width of the rectangle to make the height of the cylinder, and the volume is relatively large.

At this time, the radius of the bottom surface: decimeters.

Volume: cubic decimeters.

Take 4 decimeters as the height squared 4 = cubic decimeters.

Take the decimeter as the high square cubic decimeter.

The difference between the base area and the height is the least, and the volume is the largest.

Generally speaking, it is the length multiplied by the width, provided that the length of the bonded part is ignored.

Radius=2 2 dm.

Volume = 1 1 cubic decimeter.

1) Surround the cylinder with a height of 4 decimeters. The circumference of the base is and its radius is about.

The volume is 2) to be high and enclosed into a cylinder. The circumference of the base is 4dm, and its radius is 4 ( dm

The volume is obvious, and the volume of the two is not equal.

Is it not the same as the physical pole?

It's not the same. The length of 6 decimeters is the circumference, the radius = 6 2 * decimeters, and the height is 4 decimeters.

Volume: cubic decimeters.

The width of 4 decimeters is the circumference, the radius = 4 2 * decimeters, and the height is 6 decimeters.

Volume: cubic decimeters.

The latter is small The volume of the cylinder = the base area x the height.

rr hr is the base radius, pi, h is the high.