To produce a batch of parts, A makes 18 parts every day, and B alone makes 12 days to complete. Now A and B are working together. When the task is completed, the ratio of the number of parts produced by A and B is 1:3. How many parts did A produce in total?
生产一批零件，甲每天做18个，乙单独做12天完成．现甲、乙两人合做，完成任务时，甲、乙生产零件数量之比为1：3，甲一共生产了零件多少个？
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(3/4) / (1/12)</gadget>
<output>9</output>

<gadget id="calculator">9 * 18</gadget>
<output>162</output>

<result>162</result>