Xingxing Toys Factory plans to produce a batch of toy cats for Bai'an shopping mall, producing 500 pieces per day, and the task can be completed in 20 days. Later, according to the requirements of the shopping mall, it was completed 4 days in advance. How many pieces are actually produced on average per day?
星星玩具厂计划生产一批玩具猫给百安商场，每天生产500件，20天可完成任务．后来根据商场要求提前4天完成．实际平均每天生产多少件？
<gadget id="calculator">20 - 4</gadget>
<output>16</output>

<gadget id="calculator">20 / 16</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">500 * (5/4)</gadget>
<output>625</output>

<result>625</result>