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प्रश्न
The radius of a circle is 21 cm. Find the circumference (Take π = `3 1/7`).
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उत्तर
Given, radius (r) = 21 cm and π =`22/7`
Circumference of the circle = 2πr
= `2xx22/7xx21` cm
= 2 × 22 × 3 cm
= 132 cm
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