Mensurationmedium · Past Paper
If the radius of a cone is tripled and slant height is halved, the CSA becomes:
A1.5 times
B3 times
C4.5 times
DEqual
✓ Correct Answer: A — 1.5 times
New CSA = π(3r)(l/2) = 1.5 (πrl). It becomes 1.5 times.
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