A cylindrical timber is 2.8 meters long and sawn into two sections. The surface area increases by 6.28 square decimeters. The volume of this timber is () cubic decimeters

A cylindrical timber is 2.8 meters long and sawn into two sections. The surface area increases by 6.28 square decimeters. The volume of this timber is () cubic decimeters

Bottom area = 6.28 △ 2 = 3.14 square decimeters
Length = 28 decimeters
Volume = 3.14 × 28 = 87.92 cubic decimeter
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A 1.5-meter-long wood is sawn into three sections on average, and the surface area is increased by 4.8 square decimeters. How many cubic decimeters is the original volume of this wood?

Sawing into 3 sections, increasing the surface area by 4 sections (the area is 4.8 square decimeters)
1.5m = 15m
1 section area = 4.8 △ 4 = 1.2 square decimeter
The original volume of this wood = 1.2 × 15 = 18 cubic decimeters

The volume of the combination is 64 cubic decimeters, the volume of the cylinder (), the volume of the cone ()?
Let me know

Volume of cylinder = bottom area × height
The volume of the cone = the area of the bottom × the height △ 3
Let (bottom area × height) be a, a + a divide by 3 = 64, that is, four thirds of a = 64, and the solution is a = 48
therefore
Cylinder volume = 48 cubic decimeter
The volume of the cone = 48 divided by 3 = 16 cubic decimeters

For a cylinder or cone with equal base and height, if the volume of the cylinder is 8 cubic decimeters more than that of the cone, then the volume of the cylinder is (), and the volume of the cone is ()
In a hurry

S Cylinder = bottom area × height
S cone = base area × height / 3 = s Cylinder / 3
S cylinder-s cone = 2 / 3 * s Cylinder = 8 M3
S = 12 cubic meters
S cone = 12 / 3 = 4 m3

Use 7200 cubic decimeter steel to cast a cylinder and a cone. The height of the cylinder is 3 / 4 of that of the cone, and the bottom radius of the cone is 1 / 2 of that of the circle

Let R be the base radius of the cone and H be the height, then π (2R) * 2 * (3 / 4) H + (1 / 3) π R * 2H = 7200
π R * 2H = 2160; cylinder volume = π (2R) * 2 * (3 / 4) H = 3 * π R * 2H = 3 * 2160 = 6480 cubic decimeter

Cut the cylinder into the largest cone. The volume cut off is 10 cubic decimeters. The cylinder volume is (), and the cone volume is ()

Cylinder volume: 10 / 2 / 3 = 15 cone volume: 15 × 1 / 3 = 5

The volume difference between a cone and its cylinder with the same base and height is 169.56 cubic decimeters. It is known that the diameter of the bottom of the cylinder is 6 decimeters. What is the height of the cylinder?

V cone = Πr ^ 2H / 3
V cylinder = Πr ^ 2H
Equal base and equal height, vcylinder / 3 = vcylinder
Vcylinder-vcylinder = vcylinder-vcylinder / 3 = 2vcylinder / 3 = 169.56
Vcylinder = 254.34
=3.14*(6/2)^2H
The solution is h = 9 (decimeter)

It is known that the volume difference between a cone and a cylinder is 18 cubic meters, and the volume of a cylinder is 18 cubic meters______ The volume of the cone is______ ．

The volume of cone: 18 △ 2 = 9 (cubic meters) the volume of cylinder: 9 × 3 = 27 (cubic meters) answer: the volume of cylinder is 27 cubic meters, the volume of cone is 9 cubic meters, so the answer is: 27 cubic meters; 9 cubic meters

A cylinder and a cone have the same base and height, and the volume sum is 196 cubic decimeters. The volume of a cylinder is () cubic decimeters less than that of a cone?
Add reason to the formula, add reason to the good one

The volume of a cylinder is three times that of a cone
Now the volume sum is 196, the cylinder takes three parts, the cone takes one part, and each part is 196 / 4 = 49
Cylinder volume = 49 * 3 = 147 cone volume = 49
It should be that the cone is 147-49 less than the cylinder = 98

The volume of a cylinder is 169.56 cubic meters. What is the volume of a cone of the same height as it?

Changwa,
169.56 × 1 / 3 = 56.52 (cubic meter) = 56520 (cubic decimeter)