Master Li and Master Zhang each make 180 parts. Master Li makes 6 parts per hour, and Master Zhang makes 5 parts per hour. How many hours are they finished?
李师傅和张师傅各做180个零件，李师傅每小时做6个零件，张师傅每小时做5个零件，他们相差几小时完成？
<gadget id="calculator">180 / 5</gadget>
<output>36</output>

<gadget id="calculator">180 / 6</gadget>
<output>30</output>

<gadget id="calculator">36 - 30</gadget>
<output>6</output>

<result>6</result>