A solid metallic sphere of radius 9 cm is melted and recast into a cone whose height is four times its base radius (h=4r). Find the base radius r of the cone (in cm).
Class 10Conversion of SolidsMensuration
A9
B18
C10
D8
Step-by-Step Solution
Sphere V=34π*93. Cone V=31π*r2∗(4r)=34π*r3. Equate: 34π*93=34π*r3⇒r3=93⇒r=9 cm.
Answer: A) 9
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