The time it takes to assemble a machine has been shortened by 20% compared to the past, how much has his production efficiency improved
装配一台机器所用的时间比过去缩短了20%，他的生产效率提高了多少
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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

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