The two masters and apprentices cooperated and began to process a batch of parts at the same time. The task was completed when the apprentice finished 180 parts. Now we know that the number of parts completed by the master is 30 more than half of all the parts. To make 40 parts in an hour, how many hours did it take for the master and apprentice to complete the task?
师徒二人合作，同时开始加工一批零件，当徒弟做完180个零件时就完成了这项任务，现在我们知道，师傅完成的零件数比所有零件数的一半还多30个，师傅每小时做40个零件，师徒二人完成任务用了多少小时？
<gadget id="calculator">30 * 2</gadget>
<output>60</output>

<gadget id="calculator">180 + 60</gadget>
<output>240</output>

<gadget id="calculator">240 / 40</gadget>
<output>6</output>

<result>6</result>