It takes 16 minutes for the master to manufacture a part, and 20 minutes for the apprentice. How much slower is the work efficiency of the apprentice than the master?
制造一个零件，师傅要16分钟，徒弟要20分钟，徒弟的工作效率比师傅慢多少
<gadget id="calculator">1 / 16</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/16) - (1/20)</gadget>
<output>1/80 = around 0.0125</output>

<gadget id="calculator">(1/80) / (1/16)</gadget>
<output>1/5 = around 0.2</output>

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