Cut a 1.8-meter-long cuboid wood into two sections. The surface area is increased by 4 square decimeters. What is the volume of the cuboid wood

Cut a 1.8-meter-long cuboid wood into two sections. The surface area is increased by 4 square decimeters. What is the volume of the cuboid wood

The surface area increases the area of two cross sections, 1.8 m = 18 decimeters
The area of a cross section is equal to 4 △ 2 = 2 square decimeters
The volume of this wood = cross-sectional area × length = 2 × 18 = 36 cubic decimeters

A 3-meter-long cuboid wood is cut into 3 sections on average, and the surface area is increased by 0.36 square decimeter. What is the volume of this wood cubic decimeter?

It is cut into three sections, and four sections are added,
Cross sectional area = 0.36 △ 4 = 0.09 square decimeter
Volume = section area X length = 0.09x3 * 10 = 2.7 cubic decimeter

Use eight cube with edge length of 1 decimeter to form a cuboid. How many square decimeters is the minimum surface area of the cuboid? How many square decimeters is the maximum surface area of the cuboid

Minimum: 1 × 1 × 4 × 2 + 1 × 1 × 2 × 4=
Maximum: 1 × 1 × 4 × 4 + 1 × 1 × 2=
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