InterviewSolution
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A circle of radius is equal to the diagonal of the square whose perimeter is numerically √3 times the area of an equilateral triangle with circumradius 4√3 cm. Find double the area of the circle with that radius.1. 1458π cm22. 2916π cm23. 729π cm24. 2216π cm2 |
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Answer» Correct Answer - Option 2 : 2916π cm2 Given: Radius of circle = Diagonal of square Perimeter of Square = √3 × area of equilateral triangle Circumradius of equilateral triangle = 4√3 cm Formulas Used: CircumRadius (R) = Side of equilateral triangle/√3 Area of Equilateral Triangle = (√3/4) × (Side)2 Perimeter of Square = 4 × Side of square(a) Diagonal of Square = √2 × Side of Square Area of circle = π × (Radius)2 Calculation: Side of equilateral triangle = √3 × 4√3 = 12 cm Area of Equilateral Triangle = (√3/4) × (12)2 = 36√3 cm2 Here it is given that perimeter of square is √3 times the Area of equilateral triangle Perimeter of Square = 4 × a = √3 × 36√3 = 108 cm Side of Square (a) = 108/4 = 27 cm Diagonal of Square = √2 × a = √2 × 27 = 27√2 cm Radius of Circle (r) = Diagonal of square ⇒ r = 27√2 cm Area of circle = π × (27√2)2 = 1458π Double the area of circle = 2 × 1458π = 2916π ∴ Double the area of the circle is 2916π. |
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