Question
A metal wire when bent in the form of a square encloses
an area 1089 cm 2 , if the same wire is bent in the form of a circle, then its area is?Solution
Area of square = 1089 cm² = a 2 so a = 33 cm & square is bent in form of a circle , so perimeter of square will be equal to circumference of the circle . It means , 2πR = 4a or 2 × 22/7 × R 2 = 4 × 33 so R = 21cm & area of the circle = πR 2 = 22/7 R 2 = 22/7 × 21 × 21 = 1386 cm²
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