Question
The surface area of a sphere is $616\ cm^2$. Find its radius.
✓
Answer
The surface area of sphere $= 616\ cm^2$
We know that
$4\pi\text{r}^2=616$
$\text{r}^2=\frac{616}{4\pi}$
Taking square root both the side
$\sqrt{\text{r}^2}=\sqrt{\frac{616}{4\pi}}$
$\text{r}=7\text{cm}$
We know that
$4\pi\text{r}^2=616$
$\text{r}^2=\frac{616}{4\pi}$
Taking square root both the side
$\sqrt{\text{r}^2}=\sqrt{\frac{616}{4\pi}}$
$\text{r}=7\text{cm}$
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