A and B produce the same number of certain parts at the same time. A produces 20 pieces per hour, and B produces 11 pieces per hour. When A’s task is completed, he immediately helps B make 36 pieces, and B also completes the task. , Ask: How many hours did it take A to complete his task?
甲、乙二人同时各自生产同样数量的某种零件，甲每小时生产20个，乙每小时生产11个，当甲的任务完成之后，又立即帮乙做了36个，乙也完成了任务，问：甲完成自己的任务用了几小时？
<gadget id="calculator">36 / 11</gadget>
<output>36/11 = around 3.272727</output>

<gadget id="calculator">11 / 20</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">1 - (11/20)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">(36/11) / (9/20)</gadget>
<output>80/11 = around 7.272727</output>

<gadget id="calculator">(80/11) * (11/20)</gadget>
<output>4</output>

<result>4</result>