Question
Find the area of a circle whose diameter is: $7\ km.$
✓
Answer
Let $r$ be the radius of the circle.
Then,$ r =\frac{7}{2}=3.5\text{km}.$
$\therefore$ Area of the circle $=\pi\text{r}^2$
$=\text{A}=\frac{22}{7}\times3.5^2\text{km}^2$
$=\text{A}=38.5\text{km}^2$
Then,$ r =\frac{7}{2}=3.5\text{km}.$
$\therefore$ Area of the circle $=\pi\text{r}^2$
$=\text{A}=\frac{22}{7}\times3.5^2\text{km}^2$
$=\text{A}=38.5\text{km}^2$
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