Question

Q.5 the volume and the surface area of a sphere are numerically equal. Then find the radius of
sphere.
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Answer 1

Volume of sphere= $\frac{4}{3} \pi r^3$

Surface Area of sphere= 4$\pi r^2$

Given that,

$\frac{4}{3}\pi r^3= 4\pi r^2$

Cancelling pie on both sides, we get

$\frac{4}{3}r= 4$

$r=\frac{4*3}{4}$

Therefore, r=3