In a 200-meter race on a circular track with a width of 1.25 meters and a length of 400 meters, the starting line of each next track must be how many meters ahead of the previous one.
在跑道宽为1.25米，长400米的环形跑道上进行200米比赛，每下一道的起跑线都要比前一道提前多少米．
<gadget id="calculator">3.14 / 2</gadget>
<output>1.57</output>

<gadget id="calculator">1.25 * 2 * 1.57</gadget>
<output>3.925</output>

<result>3.925</result>