A rope, cut its (1/4) for the first time, and cut its (1/5) for the second time. It is known that the length of the second cut is 1 meter shorter than the first time. How long was this rope originally?
一根绳子，第一次剪下它的(1/4)，第二次剪下它的(1/5)，已知第二次剪下的长度比第一次短1米．这根绳子原有多长？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/4) - (1/5)</gadget>
<output>1/20 = around 0.05</output>

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

<result>20</result>