To build a canal of 67 kilometers, there are still 42 kilometers left to be repaired. How many kilometers have been repaired? (Solution of column equation)
修一条水渠67千米的水渠，还剩42千米没有修，已经修了多少千米？(列方程解)
<gadget id="calculator">67 - 42</gadget>
<output>25</output>

<result>25</result>