Master Li (1/3) can process 5 parts in an hour. How many minutes does it take him to process one part on average?
李师傅(1/3)小时可加工5个零件，他加工一个零件平均用多少分钟．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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

<result>4</result>