Mensurationeasy · Past Paper
A metallic sphere of radius 10.5 cm is melted and recast into small cones of radius 3.5 cm and height 3 cm. This question relates to volume, but what is the total surface area of the original sphere?
A1386 cm²
B1400 cm²
C1500 cm²
D1286 cm²
✓ Correct Answer: A — 1386 cm²
TSA = 4πr² = 4 * (22/7) * 10.5 * 10.5 = 1386 cm².
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