Mensurationeasy · Past Paper
If the radius of the base of a cone is halved, keeping the height same, what is the ratio of the volume of the reduced cone to that of the original cone?
A1:4
B1:2
C1:8
D1:3
✓ Correct Answer: A — 1:4
V = 1/3 π r² h. If r becomes r/2, V' = 1/3 π (r/2)² h = 1/4 V. Ratio is 1:4.
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