The sum of the volumes of a cylinder and a cylinder with the same height and bottom is 24 square decimeters. What are the volumes of a cylinder and a cone?

The sum of the volumes of a cylinder and a cylinder with the same height and bottom is 24 square decimeters. What are the volumes of a cylinder and a cone?

Tang Xuejian YY,
Cone volume: 24 ÷ (3 + 1) = 6 (cubic decimeter)
Cylinder volume: 6 × 3 = 18 (cubic decimeter)

After sawing a 2-meter-long cylindrical wood into three small columns, their total surface area increased by 12.56 square decimeters
How many cubic decimeters is the product?
It's a cylindrical piece of wood. If you saw it into three sections, the surface area will increase by 12.56 square decimeters. What is the volume of this 2.4 decimeter long wood?

Cut three sections, then add 2 × 2 = 4 cross sections
Then the area of a cross section is: 12.56 △ 4 = 3.14 square decimeters
3.14 × 2.4 = 7.536 cubic decimeter
A: the original volume was 7.536 cubic decimeters

The surface area of a 2-meter-long cylindrical timber increases 169.56 square decimeters after sawing into four sections

Cylindrical timber, sawn into four sections, increases the surface area by six circles
As the surface area increases by 169.56 square decimeters, the area of each circle is 169.56 △ 6 = 28.26 square decimeters
The volume of this cylinder is: 20 × 28.26 = 565.2 cubic decimeter