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प्रश्न
Two cubes, each of volume 64 cm3, are joined end to end. Find the total surface area of the resulting cuboid.
उत्तर
Volumebof the cube = a3
Therefore,
a3 = 64
⇒ a3 = (4)3
⇒ a = 4
Each side of the cube = 4 cm
Then,
length of the cuboid ⇒ (2 × 4)
Breadth of the cuboid = 4 cm
Height of the cuboid = 4 cm
Total surface area of the cuboid = 2(lb+bh+lh)
=2[(8 × 4)+(4 × 4)+(8 × 4)]cm2
=(2 × 80) cm2
= 160 cm2
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