A circle is divided into several equal parts along the radius and put together to form an approximate rectangle. The perimeter of the rectangle is 6 cm longer than the perimeter of the circle. What is the perimeter of the circle in centimeters?
一个圆沿半径分成若干等分，拼成一个近似的长方形，长方形的周长比圆的周长多6厘米，这个圆的周长是多少厘米．
<gadget id="calculator">3.14 * 6</gadget>
<output>18.84</output>

<result>18.84</result>