There is a 400-meter sports field. There are 4 circular tracks, each of which is 1.25 meters wide. Now, for a 200-meter race, the starting line needs to be determined. How many meters is the difference between the first starting line and the second starting line?
有一个400米的运动场，共有4条环形跑道，每条道宽1.25米，现在要进行200米的赛跑，需确定起跑线，问第一道起跑线与第二道起跑线相差多少米？
<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>