Mensurationmedium · Past Paper
If the radius of a cylinder is doubled and the height is halved, what is the ratio of the new volume to the original volume?
A1:1
B2:1
C4:1
D1:2
✓ Correct Answer: B — 2:1
V1 = πr²h. V2 = π(2r)²(h/2) = π(4r²)(h/2) = 2πr²h. Ratio V2:V1 = 2:1.
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