To process 600 pieces of the same electrical equipment, after 12 days of processing, the ratio of the number of processed pieces to the number of unprocessed pieces is 1:3. According to this work efficiency, how many days will it take to finish processing this batch of equipment?
要加工600件一样的电气设备，加工了12天后，已加工的件数与未加工的件数的比是1：3，按这样的工作效率，加工完这批设备，一共要用多少天？
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">1 / 4 / 12</gadget>
<output>1/48 = around 0.020833</output>

<gadget id="calculator">1 / (1/48)</gadget>
<output>48</output>

<result>48</result>