Master Li plans to make 600 parts, which can be completed every day (2/15), how many days will it be completed?
李师傅计划做600个零件，每天可以完成(2/15)，多少天修完．
<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">1 / (2/15)</gadget>
<output>15/2 = around 7.5</output>

<result>15/2 = around 7.5</result>