The tortoise and the hare race, the whole journey is 400 meters, the tortoise climbs 2 meters per minute, and the rabbit runs 100 meters per minute. There are still 50 meters to the finish line. How many minutes did the rabbit sleep on the way?
龟兔赛跑，全程400米，乌龟每分钟爬2米，兔子每分钟跑100米，发令枪响后，兔子遥遥领先，很骄傲，在途中美美地睡了一觉，结果乌龟到达终点时，兔子离终点还有50米，兔子途中睡了多少分钟．
<gadget id="calculator">400 / 2</gadget>
<output>200</output>

<gadget id="calculator">400 - 50</gadget>
<output>350</output>

<gadget id="calculator">350 / 100</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">200 - (7/2)</gadget>
<output>393/2 = around 196.5</output>

<result>393/2 = around 196.5</result>