A job started on April 1st and was originally scheduled to be completed in one month. During the actual construction, the task was completed on April 25th. How much work efficiency has been improved.
一项工作，4月1日开工，原定一个月完工，实际施工时，4月25日完成任务，工作效率提高多少．
<gadget id="calculator">1 / 25</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/25) - (1/30)</gadget>
<output>1/150 = around 0.006667</output>

<gadget id="calculator">(1/150) / (1/30)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>