If a worker makes 120 parts in 3 hours, according to this calculation, how many hours can make 200 parts.
一个工人3小时做120个零件，照这样计算，多少小时可做200个零件．
<gadget id="calculator">120 / 3</gadget>
<output>40</output>

<gadget id="calculator">200 / 40</gadget>
<output>5</output>

<result>5</result>