Master Wang processes a batch of parts. The ratio of the number of parts processed on the first day to the total number of parts is 1:3. If another 30 parts are processed, the number of remaining parts will be the same as the number of finished parts. How many parts are there in total?
王师傅加工一批零件，第一天加工的零件个数与零件总数的比是1：3，如果再加工30个零件，剩下的零件个数就和加工完的零件个数一样多，这批零件一共有多少个？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/2) - (1/3)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">30 / (1/6)</gadget>
<output>180</output>

<result>180</result>