Question
A circular wire of diameter 70 cm is folded in the shape
of a rectangle whose sides are in the ratio 3:2. Find the area enclosed by the rectangle.Solution
Using the formula, Area = lb & D = 2r and A = πr² Radius of circular wire = 70/2 = 35 cm Circumference of wire = 2πr = 2 x (22/7) x 35 = 220 cm Let the length and breadth of rectangle be 3x & 2x cm respectively. Therefore, perimeter of rectangle = 2(3x + 2x) = 10x According to the question, 10x = 220 ⇒ x = 220/10 = 22 Therefore, length of rectangle = 3x = 3 x 22 = 66 cm Breadth of rectangle = 2x = 2 x 22 = 44 cm Area = 66 x 44 = 2904 cm²
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