Question

if the surface area of a sphere is 144 pi cm2,then its radius is?

Answer 1

CSA of sphere=4pi r square
144pi =4*22/7*r square
144pi*7/4*22=r squre
126*22/7/11=r sqare

Answer 2

Answer:

$Radius\: of \:the \:sphere (r) = 6\: cm$

Step-by-step explanation:

$Let \: the \: radius \: of \: a \: sphere = r \: cm$

$\boxed {Surface \: Area \: of \: the \: sphere (A)=4\pi r^{2}}$

$Here,\\ A = 144 \pi \: cm^{2}\: (given )$

$\implies 4\pi r^{2}=144\pi \: cm^{2}$

$\implies r^{2}=\frac{144\pi \: cm^{2}}{4 \pi}$

$\implies r^{2}=36\: cm^{2}$

$\implies r = \sqrt{36 \: cm^{2}}$

$\implies r = 6 \: cm$

Therefore,

$Radius\: of \:the \:sphere (r) = 6\: cm$

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