A canal, 1200m long, has been repaired (1/5), how many meters are left to be repaired?
一条水渠，长1200m，已经修了(1/5)，还剩多少米没修？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1_200 * (4/5)</gadget>
<output>960</output>

<result>960</result>