In order to help Guizhou fight against drought, the factory rushed to produce a batch of water pipes. The first workshop completed (1/5) of this batch of water pipes, the second workshop completed (1/4) of this batch of tents, and there are still a few of this batch of tents left. How much is not completed?
为了帮助贵州抗旱，工厂赶制一批水管，第一车间完成了这批水管的(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有完成？
<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>