if the area of a circle decreases by 20 % , then the radius of a circle decreases by
if area of a circle decreased by x % then the radius of a circle decreases by ( 100 − 10 √ 100 − x ) % = ( 100 − 10 √ 100 − 20 ) % = ( 100 − 10 √ 80 ) % = 100 - 89 = 11 % answer d
multiply(subtract(const_1, sqrt(divide(subtract(const_100, 20), const_100))), const_100)