Fold a rope into 5 strands and 6 strands respectively. If the 5 strands are 20 cm longer than the 6 strands, what is the length of the rope in centimeters?
把一根绳子分别等分折成5股和6股，如果折成5股比6股长20厘米，那么这根绳子的长度是多少厘米．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/5) - (1/6)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">20 / (1/30)</gadget>
<output>600</output>

<result>600</result>