In order to help the victims of the earthquake in Sichuan, the factory rushed to make a batch of disaster relief tents. The first workshop completed (1/5) of this batch of tents, the second workshop completed (1/4) of this batch of tents, and the remaining batch of tents What percentage of it is not completed?
为了帮助四川地震灾民，工厂赶制一批救灾帐篷，第一车间完成了这批帐篷的(1/5)，第二车间完成了这批帐篷的(1/4)，还剩下这批帐篷的几分之几没完成？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/5) - (1/4)</gadget>
<output>11/20 = around 0.55</output>

<result>11/20 = around 0.55</result>