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Question
Find the area of the shaded region in Fig. 3, where arcs drawn with centres A, B, C and D intersect in pairs at mid-points P, Q, R and S of the sides AB, BC, CD and DA respectively of a square ABCD of side 12 cm. [Use π = 3.14]
Solution
Area of the shaded region = = Area of the square ABCD − 4 (Area of the quadrant)
`= (12)^2 - 4 x (90^@/360^@ xx pi xx (6)^2)`
`= 144 - 4 xx (1/4 xx pi xx 36)`
`= 144 - 36pi`
= 144 - 36 x 3.14
`= 30.96 cm^2`
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