There are two ropes of the same length. The first rope is cut into 5 pieces on average, and the second rope is cut into 7 pieces on average. Each piece of the first rope is 2 meters longer than that of the second rope. How long is each rope in meters?
有两根同样长的绳子，第一根平均剪成5段，第二根平均剪成7段，第一根剪成的每段比第二根剪成的每段长2米．原来每根绳子长多少米．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">(1/5) - (1/7)</gadget>
<output>2/35 = around 0.057143</output>

<gadget id="calculator">2 / (2/35)</gadget>
<output>35</output>

<result>35</result>