One job, A can complete (1/6) of it in 4 hours, then how many hours does A need to complete this job.
一件工作，甲4小时可以完成它的(1/6)，那么甲完成这件工作需多少小时．
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">4 / (1/6)</gadget>
<output>24</output>

<result>24</result>