The school has a playground with a circle of 200m and a track width of 1.5m. To conduct a 400m run (that is, run two laps) on this field, how many meters should the starting line advance in turn?
学校有一运动场，一圈为200m，跑道宽为1.5m．要在这个场上举行400m跑(即跑两圈)，起跑线该依次提前多少米？
<gadget id="calculator">6 * 3.14</gadget>
<output>18.84</output>

<result>18.84</result>