A factory produces a batch of lathes, and plans to produce 180 lathes per day, which will be completed in 20 days. The actual production is 200 units per day, how many days in advance is it actually completed?
某工厂生产一批车床，计划每天生产180台，20天完成．实际每天生产200台，实际提前多少天完成？
<gadget id="calculator">20 / 200</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">180 * (1/10)</gadget>
<output>18</output>

<gadget id="calculator">20 - 18</gadget>
<output>2</output>

<result>2</result>