To build a road with a length of 3 kilometers, the full length (7/10) has been built, and how many meters are left to be repaired.
要修一条长3千米的公路，已经修了全长的(7/10)，还剩多少米没修．
<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">3 * 1_000 * (3/10)</gadget>
<output>900</output>

<result>900</result>