Dig a 180-meter-long canal, and the full length (3/5) has been dug. How many meters are left?
挖一条180米长的水渠，已经挖了全长的(3/5)，还剩下多少米？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">180 * (2/5)</gadget>
<output>72</output>

<result>72</result>