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प्रश्न
विकल्प
\[14\pi\]
\[\frac{7}{\pi}\]
7\[\pi\]
\[\frac{14}{\pi}\]
उत्तर
Let r be the radius of the circle.
Circumference of the circle : Area of the circle = 2 : 7
\[\Rightarrow \frac{2\pi r}{\pi r^2} = \frac{2}{7}\]
\[ \Rightarrow \frac{1}{r} = \frac{1}{7}\]
\[ \Rightarrow r = 7\]
∴ Circumference of the circle = \[2\pi r = 2\pi \times 7 = 14\pi\]
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