To build a road, the full length (7/10) has been built, what fraction of the full length is the rest?
要修一条公路，已经修了全长的(7/10)，剩下的比完成的少全长的几分之几？
<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 - (7/10)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(7/10) - (3/10)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>