The road construction team repaired a 2-kilometer-long sewer. They repaired (3/5) kilometers on the first day and (7/10) kilometers on the second day. How many kilometers are left to be repaired?
修路队修一条长2千米的下水道，第一天修了(3/5)千米，第二天修了(7/10)千米，还剩下多少千米没修？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">2 - (3/5) - (7/10)</gadget>
<output>7/10 = around 0.7</output>

<result>7/10 = around 0.7</result>