A wire uses up the full length (2/9) for the first time, (4/9) for the second time, and (1/9) for the third time. How much of this wire is left?
一根铁丝第一次用去全长的(2/9)，第二次用去全长的(4/9)，第三次用去全长的(1/9)．这根铁丝还剩几分之几？
<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

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

<gadget id="calculator">1 - (2/9) - (4/9) - (1/9)</gadget>
<output>2/9 = around 0.222222</output>

<result>2/9 = around 0.222222</result>