Difficulty: Medium
Correct Answer: 286 cm2
Explanation:
Introduction / Context:Melting conserves volume. We first find the cube’s side from equal volume, then compute both surface areas and take the difference. This tests volume conservation and area formulas.
Given Data / Assumptions:
Concept / Approach:
Step-by-Step Solution:
V_block = 27*8*1 = 216 cm3 ⇒ a = 6 cm (since 6^3 = 216).SA_block = 2*(27*8 + 8*1 + 27*1) = 2*(216 + 8 + 27) = 502 cm2.SA_cube = 6*a^2 = 6*36 = 216 cm2.Difference = 502 − 216 = 286 cm2.Verification / Alternative check:
Recompute each product to avoid arithmetic slips; sums match.Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
286 cm2
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