Q14 of 37 Page 13

The area of a circle is 78.5 sq.cm. Calculate the circumference of the circle [Taken π=3.14].

Given: Area of circle = 78.5cm2


πr2 = 78.5


⇒ 3.14 r2 = 78.5



⇒ r2 = 25


⇒ r = ± 5


⇒ r = 5cm


[taking positive root, because radius can’t be negative]


Now, circumference of circle = 2πr


= 2 × 3.14 × 5


= 31.4cm


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