Hongfeng Toy Factory originally planned to produce 450 dolls per day, and the task could be completed in 20 days. Actually produce 50 more per day, how many days can actually complete the task?
红丰玩具厂原计划每天生产布娃娃450个，20天可以完成任务．实际每天多生产50个，实际多少天可以完成任务？
<gadget id="calculator">450 * 20</gadget>
<output>9_000</output>

<gadget id="calculator">450 + 50</gadget>
<output>500</output>

<gadget id="calculator">9_000 / 500</gadget>
<output>18</output>

<result>18</result>