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# Find the area of the shaded region in Fig. 12.21, if ABCD is a square of side 14 cm and APD and BPC are semicircles.Q.4

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What is the best solution of ncert class 10 areas related to circles of exercise 12.3 question number 4. Please give me the easiest and simplest solution of this question .Find the best solution of this important question.Find the area of the shaded region in Fig. 12.21, if ABCD is a square of side 14 cm and APD and BPC are semicircles.

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1. It is given that OAB is an equilateral triangle having each angle as 60Â°

Area of the sector is common in both.

Radius of the circle = 6 cm.

Side of the triangle = 12 cm.

Area of the equilateral triangle = (âˆš3/4) (OA)2= (âˆš3/40Ã—122Â = 36âˆš3 cm2

Area of the circle = Ï€R2Â = (22/7)Ã—62Â = 792/7 cm2

Area of the sector making angle 60Â° = (60Â°/360Â°) Ã—Ï€r2Â cm2

= (1/6)Ã—(22/7)Ã— 62Â cm2Â = 132/7 cm2

Area of the shaded region = Area of the equilateral triangle + Area of the circle â€“ Area of the sector

= 36âˆš3 cm2Â +792/7 cm2-132/7 cm2

= (36âˆš3+660/7) cm2

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