After producing a batch of parts, after improving the technology, the same number of parts can be produced, and the time is saved by 20%. How much is the work efficiency improved now?
生产一批零件，改进技术后，生产同样多的零件，时间节省了20%，现在的工作效率提高了多少
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 * (4/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 / (4/5)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">(5/4) - 1</gadget>
<output>1/4 = around 0.25</output>

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

<result>1/4 = around 0.25</result>