Q12 of 43 Page 223

The circumference of a circle is 31.4 cm. Find the radius and the area of the circle. (Take π = 3.14)

It is given in the question that,

Circumference of circle = 31.4 cm

We know that,

Circumference of the circle = 2πr

∴ 31.4 = 2 × 3.14 × r

31.4 = 6.28 × r

⇒ r = 31.4/6.28

⇒ r = 5 cm

Area of the circle = πr2

= 3.14 × 5 × 5

= 3.14 × 25

= 78.5 cm2

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