2m long iron wire, first cut off (1/3), then cut off (1/6), how much of it is left.
2m长的铁丝，先剪去它的(1/3)，再剪去它的(1/6)，还剩下它的多少．
<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>