The width of the ring is 1.5 times the radius of the inner circle, and the area of the ring is 210 square centimeters. What is the area of the inner circle in square centimeters?
环宽是内圆半径的1.5倍，环形面积是210平方厘米，内圆的面积是多少平方厘米．
<result>40</result>