After the reform of a certain factory, the number of personnel has decreased by 1/5, the output has increased by 20% compared to the original, and how much the work efficiency has been improved.
某工厂改革后，人员减少了(1/5)，产量比原来增加了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 / 5</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">(6/5) / (4/5)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) - 1</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>