Question
The surface area of a solid metallic sphere is $2464 \ cm^2.$ It is melted and recast into solid right circular cones of radius $ 3.5 \ cm$ and height $7 \ cm.$ Calculate: the radius of the sphere $($Take $\pi = 22/17)$
✓
Answer
Total surface area of the sphere $= 4\pi r^2,$ where r is the radius of the sphere.
Thus,
$4 \pi r^2=2464 \ cm ^2$
$\Rightarrow 4 \times \frac{22}{7} \times r^2=2464$
$\Rightarrow r^2=196$
$\Rightarrow r=14 \ cm $
Thus,
$4 \pi r^2=2464 \ cm ^2$
$\Rightarrow 4 \times \frac{22}{7} \times r^2=2464$
$\Rightarrow r^2=196$
$\Rightarrow r=14 \ cm $
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