A factory improves management, reduces the number of people (1/4), but increases output by 20%. How much work efficiency has been improved?
某厂改善管理，人数减少(1/4)，产量却增加20%，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>6/5 = around 1.2</output>

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

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(6/5) / (3/4)</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">(8/5) - 1</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/5) / 1</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>