person takes a train and falls asleep 50% of the way. When he wakes up, he finds that the remaining distance is 50% of the distance he traveled before going to sleep. What percentage of the total distance is the remaining distance?
一个人乘火车，行了全程的50%时他睡着了，醒来时发现，剩下的路程是他睡觉前所行路程的50%．剩下的路程是全程的百分之几？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * (1/2)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>