A rope is cut off (5/7), and the rest is 18m shorter than the cut one. How long is this rope in meters?
一条绳子剪去(5/7)，剩下的比剪去的短18m，这条绳子长多少米？
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">1 - (5/7)</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">(5/7) - (2/7)</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">18 / (3/7)</gadget>
<output>42</output>

<result>42</result>