An electric bicycle factory completed (3/5) of the annual production plan in the first half of 2012, and completed 45% of the annual production plan in the second half of the year. How much did the factory overfulfill the plan in 2012?
某电动自行车厂2012年上半年完成全年生产计划的(3/5)，下半年完成全年生产计划的45%．该厂2012年超额完成计划的多少．
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">45 / 100</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">(9/20) - 1</gadget>
<output>-11/20 = around -0.55</output>

<gadget id="calculator">(3/5) + (-11/20)</gadget>
<output>1/20 = around 0.05</output>

<result>1/20 = around 0.05</result>