A task can be completed in 4 hours, then how many hours can be completed (1/2) of this task.
一项任务4小时可以完成，那么多少小时可以完成这项任务的(1/2)．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/2) / (1/4)</gadget>
<output>2</output>

<gadget id="calculator">4 / 2 / 1</gadget>
<output>2</output>

<result>2</result>