A rope is 4 meters long, (2/5) meters are used for the first time, and the remaining (1/9) is used for the second time, how many meters are used for the second time?
一根绳子长4米，第一次用去(2/5)米，第二次用去剩下的(1/9)，第二次用去多少米？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">4 - (2/5)</gadget>
<output>18/5 = around 3.6</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">(18/5) * (1/9)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>