It takes 10 hours for A to process a batch of parts alone, and 15 hours for B to process alone. Now A and B work together. When completing the task, A processes 30 more parts than B. How many parts are there in total?
加工一批零件，甲单独加工需要10小时，乙单独加工需要15小时，现在甲、乙两人合作，完成任务时，甲比乙多加工30个，这批零件共有多少个？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/10) + (1/15)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / (1/6)</gadget>
<output>6</output>

<gadget id="calculator">(1/10) - (1/15)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">30 / 6 / (1/30)</gadget>
<output>150</output>

<result>150</result>