The master and apprentice jointly produce a batch of parts, and the apprentice produces 30 per hour. The ratio of the master-student work efficiency is 3:2. After 3 hours of joint production, there are still (2/5) of this batch of parts. Find this batch How many parts are there?
师徒共同生产一批零件，徒弟每小时生产30个，师徒工作效率的比是3：2，两人共同生产3小时后，还剩下这批零件的(2/5)，求这批零件有多少个？
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">30 * (3/2)</gadget>
<output>45</output>

<gadget id="calculator">30 + 45</gadget>
<output>75</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">3 / (3/5)</gadget>
<output>5</output>

<gadget id="calculator">75 * 5</gadget>
<output>375</output>

<result>375</result>