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Radii of the circles are given below, find their areas.

(1) 28 cm

(2) 10.5 cm

(3) 17.5 cm

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#### Solution

(1) 28 cm

Ar = πr² = π x (28)²

= `22/7 xx 28 xx 28`

= 2464 sq cm

(2) 10.5 cm

Ar = πr² = π x (10.5)²

= `22/7 xx 10.5 xx 10.5`

= 346.5 sq cm

(3) 17.5 cm

Ar = πr² = π x (17.5)²

= `22/7 xx 17.5 xx 17.5`

= 962.5 sq cm

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