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Question
From a circular sheet of radius 4 cm, a circle of radius 3 cm is removed. Find the area of the remaining sheet. (Take π = 3.14)
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Solution
Outer radius of circular sheet (R) = 4 cm
Inner radius of circular sheet (r) = 3 cm
Remaining area = πR2 - πr2
= 3.14 × 4 × 4 − 3.14 × 3 × 3
= 50.24 − 28.26
= 21.98 cm2
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