Mensurationmedium · Past Paper
If the radius of a sphere is halved, what is the ratio of the surface area of the original sphere to the new one?
A2:1
B4:1
C1:4
D8:1
✓ Correct Answer: B — 4:1
Area A ∝ r². Original: A, New: (1/2)²A = 1/4 A. Ratio = 1 : (1/4) = 4:1.
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