The area of a circle is 394.24 cm2. Calculate : (i) the radius of the circle, (ii) the circumference of the circle.

Question

KnowledgeBoat · Accepted Answer

(i) Let the radius of circle be r cm. Given, Area = 394.24 cm2 Area of circle = πr2 ⇒ 394.24 = × r2 ⇒ r2 = ⇒ r2 = 125.44 ⇒ r = ⇒ r = 11.2 cm. Hence, radius = 11.2 cm. (ii) Circumference of circle = 2πr = 2 × × 11.2 = 2 × 22 × 1.6 = 70.4 cm. Hence, circumference = 70.4 cm.

Mathematics

The area of a circle is 394.24 cm². Calculate :
(i) the radius of the circle,
(ii) the circumference of the circle.

Mensuration

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