Question
The radius of a circle is x meters, and the side of a
square is x + 5 meters. If the sum of the circumference of the circle and the perimeter of the square is 91.96 meters, find the area of the circle (in m²).( π = 3.14)Solution
Circumference of the circle = 2πx. Perimeter of the square = 4(x + 5). From the data: 2πx + 4(x + 5) = 90. Substitute π = 3.14: 2(3.14)x + 4x + 20 = 91.96 6.28x + 4x + 20 = 91.96. 10.28x = 71.96. x = 71.96 / 10.28. x = 7 meters. Area of the circle = πx². πx² = 3.14(7)². = 3.14 × 49. = 154 Correct option: a
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