Master Wang produced a batch of parts, and he completed 70%. Afterwards, another 350 parts were produced, which was 20% more than the original plan. How many parts does Master Wang plan to produce?
王师傅生产一批零件，他完成了70%．以后又生产了350个，这样比原计划超产20%，王师傅计划生产零件多少个？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(1/5) - (7/10)</gadget>
<output>-1/2 = around -0.5</output>

<gadget id="calculator">1 + (-1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">350 / (1/2)</gadget>
<output>700</output>

<result>700</result>