The dimensions of a piece of iron in the shape of a cuboid are 270 cm...
Volume of cube = volume of cuboid
= 270 x 100 x 64 = 1728000 cm3
∴ Length of one side of the cube = 120 cm
∴ Surface area of cube = 6 x 120 x 120 = 86400 cm2
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The dimensions of a piece of iron in the shape of a cuboid are 270 cm...
Given:
Dimensions of the cuboid: 270 cm x 100 cm x 64 cm
To find:
Surface area of the cube after melting and recasting
Solution:
To find the surface area of the cube, we need to determine the length of each side of the cube.
Step 1: Volume of the cuboid
The volume of the cuboid can be calculated using the formula:
Volume = Length x Width x Height
Given:
Length = 270 cm
Width = 100 cm
Height = 64 cm
Volume = 270 cm x 100 cm x 64 cm
= 1,728,000 cm³
Step 2: Side length of the cube
Since the cuboid is melted and recast into a cube, the volume of the cube will be equal to the volume of the cuboid.
Given:
Volume of the cube = Volume of the cuboid = 1,728,000 cm³
Let's assume the side length of the cube to be 'a'.
Volume of the cube = a³
Therefore, a³ = 1,728,000 cm³
To find the side length 'a', we need to find the cube root of 1,728,000.
Using a cube root calculator or simplifying manually,
a ≈ 120 cm
Step 3: Surface area of the cube
The surface area of a cube can be calculated using the formula:
Surface Area = 6a²
Given:
Side length of the cube, a = 120 cm
Surface Area = 6 x (120 cm)²
= 6 x 14,400 cm²
= 86,400 cm²
Therefore, the surface area of the cube, after melting and recasting the cuboid, is 86,400 cm².
Answer:
The correct option is (d) 86,400 cm².
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