A road has a total length of 480 meters. (1/3) of this road was built on the first day, and (1/6) of this road was built on the second day.
一条路全长480米，第一天修了这条路的(1/3)，第二天修了这条路的(1/6)，还剩这条路的多少没有修．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 - (1/3) - (1/6)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>