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The volume of a cube is equal to sum of its edges. What is the total surface area in square units?

A) 12
B) 36
C) 72
D) 144

Correct Answer:



C) 72

Description for Correct answer:

Let the edge of a square be x and sum of its edges =12x

Now, by condition, \( \Large x^{3} = 12x \) [Because, x ≠ 0] ...(i)

=> \( \Large x \left(x^{2} - 12\right) = 0 \)

=> \( \Large x^{2} = 12 \)

Its total surface area

= \( \Large 6x^{2} = 6 \times \left(12\right) = 72 \ sq \ units \)

Part of solved Volume and surface area questions and answers : >> Elementary Mathematics >> Volume and surface area

Comments

Similar Questions

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