A rope, cut off its (1/4) for the first time, and cut off the remaining (1/5) for the second time, then there are still 10 meters left, how many meters is this rope originally?
一条绳子，第一次剪去它的(1/4)，第二次剪去余下的(1/5)，这时还剩下10米，这条绳子原来有多少米？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">10 / (4/5) / (3/4)</gadget>
<output>50/3 = around 16.666667</output>

<result>50/3 = around 16.666667</result>