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प्रश्न
2 cubes each of volume 64 cm3 are joined end to end. Find the surface area of the resulting cuboid.
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उत्तर
Given that,
Volume of cubes = 64 cm3
(Edge)3 = 64
Edge = 4 cm
If cubes are joined end to end, the dimensions of the resulting cuboid will be 4 cm, 4 cm, 8 cm.
∴ Surface area of cuboids = 2(lb + bh + lh)
= 2[(4 × 4) + (4 × 8) + (4 × 8)]
= 2(16 + 32 + 32)
= 2(16 + 64)
= 2 × 80
= 160 cm2.
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