If 3 circles with a diameter of 6 cm are tied together with a rope, how many centimeters of rope may be needed for one round of tying? (two methods)
把3个直径是6厘米的圆用绳子捆在一起，捆一周可能需要多少厘米的绳子？(两种方法)
<gadget id="calculator">3.14 * 6</gadget>
<output>18.84</output>

<gadget id="calculator">6 * 3</gadget>
<output>18</output>

<gadget id="calculator">18.84 + 18</gadget>
<output>36.84</output>

<result>36.84</result>