Question
Find the circumference of a circle whose diameter is: $4.2\ cm.$
✓
Answer
We know that the circumference of a circle of radius $r$ is given by $C =2\pi\text{r}$
Here, $ d =4.2\text{cm}$
Then, $r =\frac{4.2}{2}=2.1\text{cm}$
$\Rightarrow\text{C}=2\times\frac{22}{7}\times2.1=13.2\text{cm}$
Here, $ d =4.2\text{cm}$
Then, $r =\frac{4.2}{2}=2.1\text{cm}$
$\Rightarrow\text{C}=2\times\frac{22}{7}\times2.1=13.2\text{cm}$
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