A washing machine factory planned to produce 540 washing machines in August, but actually finished it in half a month (5/9) and in the second half of the month (July 12). How many washing machines were overproduced in August?
某洗衣机厂八月份计划生产洗衣机540台，实际上半月完成了(5/9)，下半月完成了(7/12)．八月份超额生产了多少台洗衣机？
<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">7 / 12</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">(7/12) - 1</gadget>
<output>-5/12 = around -0.416667</output>

<gadget id="calculator">(5/9) + (-5/12)</gadget>
<output>5/36 = around 0.138889</output>

<gadget id="calculator">540 * (5/36)</gadget>
<output>75</output>

<result>75</result>