Divide a circle into several equal parts, and then assemble it into an approximate rectangle. It is known that the perimeter of the rectangle is 10 cm longer than the perimeter of the circle. What is the circumference of the original circle in centimeters.
把一个圆平均分成若干等份，然后把它拼成一个近似的长方形，已知长方形的周长比圆的周长多10厘米．原来圆的周长多少厘米厘米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">2 * 3.14 * 5</gadget>
<output>31.4</output>

<result>31.4</result>