An iron wire uses up the full length (2/9) for the first time, and uses up the full length (3/9) for the second time, what fraction of the iron 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(3/9)，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">3 / 9</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (2/9) - (1/3)</gadget>
<output>4/9 = around 0.444444</output>

<result>4/9 = around 0.444444</result>