A solid metallic cuboid of dimensions 12 cm × 54 cm × 72 cm is melted and converted into 8 cubes of the same size. What is the sum of the lateral surface areas (in cm2) of 2 such cubes?
A solid metallic cuboid of dimensions 12 cm × 54 cm × 72 cm is melted and converted into 8 cubes of the same size. What is the sum of the lateral surface areas (in cm2) of 2 such cubes? Correct Answer 2592
Given:
Length of cuboid = 12 cm
Breadth of cuboid = 54 cm
Height of the cuboid = 72 cm
It is converted into 8 cubes of the same size
Formula used:
Volume of the cuboid = lbh
Volume of cube = a3
Lateral surface area of the cube = 4a2
Calculation:
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According to the question
⇒ lbh = 8 × a3
⇒ (12 × 54 × 72) = 8 × a3
⇒ (12 × 54 × 9) = a3
⇒ a3 = 5832
⇒ a = 18 cm
Now,
The sum of the lateral surface area of the two such cubes = (4a2 + 4a2)
⇒ 8a2
⇒ 8 × 18 × 18 cm2
⇒ 2592 cm2
∴ The required sum is 2592 cm2