A rope, after (2/5) is used up, the remaining (2/3) is used up, and the remaining 8 meters are useless. How many meters is this rope?
一根绳子，用去(2/5)后，又用去余下的(2/3)，还剩8米没有用．这根绳子长多少米？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(3/5) * (1/3)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">8 / (1/5)</gadget>
<output>40</output>

<result>40</result>