The area of a sector is (5/18) of the area of the circle in which it is located. What is the central angle of the sector?
一个扇形面积是它所在圆面积的(5/18)，则这个扇形的圆心角是多少．
<gadget id="calculator">5 / 18</gadget>
<output>5/18 = around 0.277778</output>

<gadget id="calculator">360 * (5/18)</gadget>
<output>100</output>

<result>100</result>