The sum of radius, diameter and perimeter of a circle is 18.56cm. How many square centimeters are left after one fourth of the area of the circle is removed? 30 points is the formula

The sum of its radius, diameter and perimeter is 18.56cm
r+2r+2πr=18.56
9.28r=18.56
r=2cm
The circle area is π * R ^ 2 = 3.14x4 = 12.56cm & # 178;
One quarter of the area of this circle is removed, leaving 12.56 x 3 / 4 = 9.42 square centimeters

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