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A metal wire, when bent in the form of a...

A metal wire, when bent in the form of an equilateral triangle of largest area, enclosed an area of `484sqrt(3) cm^(2)`. If the same wire is bent into the form of a circle of largest area, find the area of circle.

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To solve the problem step by step, we will follow these steps: ### Step 1: Understand the area of the equilateral triangle We are given that the area of the equilateral triangle is \( 484\sqrt{3} \, \text{cm}^2 \). ### Step 2: Use the formula for the area of an equilateral triangle The formula for the area \( A \) of an equilateral triangle with side length \( a \) is given by: \[ A = \frac{\sqrt{3}}{4} a^2 \] We can set this equal to the given area: \[ \frac{\sqrt{3}}{4} a^2 = 484\sqrt{3} \] ### Step 3: Solve for \( a^2 \) To eliminate \( \sqrt{3} \) from both sides, we divide by \( \sqrt{3} \): \[ \frac{1}{4} a^2 = 484 \] Now, multiply both sides by 4: \[ a^2 = 1936 \] ### Step 4: Find the side length \( a \) Taking the square root of both sides gives us: \[ a = \sqrt{1936} = 44 \, \text{cm} \] ### Step 5: Calculate the perimeter of the triangle The perimeter \( P \) of the equilateral triangle is given by: \[ P = 3a = 3 \times 44 = 132 \, \text{cm} \] ### Step 6: Relate the perimeter of the triangle to the circumference of the circle The perimeter of the triangle is equal to the circumference \( C \) of the circle formed by the same wire: \[ C = 2\pi r \] Thus, we have: \[ 132 = 2\pi r \] ### Step 7: Solve for the radius \( r \) Rearranging the equation to solve for \( r \): \[ r = \frac{132}{2\pi} = \frac{66}{\pi} \] ### Step 8: Calculate the area of the circle The area \( A \) of the circle is given by: \[ A = \pi r^2 \] Substituting for \( r \): \[ A = \pi \left(\frac{66}{\pi}\right)^2 = \pi \cdot \frac{4356}{\pi^2} = \frac{4356}{\pi} \] Using \( \pi \approx \frac{22}{7} \): \[ A = \frac{4356 \times 7}{22} = 1386 \, \text{cm}^2 \] ### Final Answer: The area of the circle is \( 1386 \, \text{cm}^2 \). ---
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