The machine tool factory completed the tasks (4/9), (5/9) and (2/3) respectively in the first three months of this year. What percentage of the plan was overfulfilled in the first quarter?
机床厂今年一季度的3个月分别完成任务的(4/9)，(5/9)和(2/3)，一季度超额完成计划的几分之几？
<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

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

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

<gadget id="calculator">(4/9) + (5/9) + (-1/3)</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>