The factory plans to complete a batch of tasks in the first quarter, but it actually produced in January (1/4), February (2/5), and March (9/20). What percentage of the actual overproduction?
工厂计划第一季度完成一批任务，实际一月生产了(1/4)，二月生产了(2/5)，三月生产(9/20)，实际超产了几分之几？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">9 / 20</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">(1/4) + (2/5) + (-11/20)</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>