To build a 500-meter-long canal, it has been repaired (3/10), how many meters have not been repaired, and the number of meters that have not been repaired is more than the one that has been repaired ((())/(())).
修一条长500米的水渠，已经修了(3/10)，没有修的有多少米，没有修的比已经修的多((())/(()))．
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">500 * (7/10)</gadget>
<output>350</output>

<result>350</result>