Q. 24.4( 18 Votes )

# Find the volume of a cube whose surface area is 486 cm^{2}.

Answer :

Given: Surface Area of a Cube = 486 cm^{2}

So, firstly we find the side of a cube

Total Surface Area of a Cube = 486 = 6a^{2}

a^{2} = 81

a = = ± 9 = 9cm (side can’t be negative)

Therefore, Side of a cube = 9 cm

Now, Volume of a Cube = a^{3} = (9)^{3} = 9 × 9 × 9 = 729 cm^{3}

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