Question 211734
Area  of  circle = pi * radius ^2
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If  shaded  area  is  difference  of  two inscribed  circles,
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Difference  of  Area = Area  of  larger - Area of smaller
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A(d) = pi * R^2 -pi * r^2
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A(d) =pi(R^2-r^2)
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in this  case , R=22, r=17
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a(d) = pi*(22^2-17^2) = pi * 195 = 612.61
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check,,,A(22) = 1520.53,,,A(17) = 907.92,,,,difference is  612.61,,,,ok
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