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प्रश्न
The volume of a cube is 729 cm3. Find its surface area.
उत्तर
Let the edge of the cube be a.
AS,
Volume of the cube = 729 cm3
`rArr a^3 = 729`
`rArr a = root(3)(729)`
⇒ a = 9 cm
Now,
Surface area of the cube = 6a2
= 6 × 6 × 9
= 486 cm2
so, the surface area of the cube is 486 cm2 .
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