A chemical fertilizer factory produced a batch of chemical fertilizers. It was originally planned to be completed in 25 days. Due to the extra production of 2 tons per day, the task was completed in 20 days. How many tons is this batch of fertilizer?
一个化肥厂生产一批化肥，原计划25天完成，由于每天多生产2吨，结果20天就完成任务．这批化肥有多少吨？
<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<gadget id="calculator">25 - 20</gadget>
<output>5</output>

<gadget id="calculator">40 / 5</gadget>
<output>8</output>

<gadget id="calculator">25 * 8</gadget>
<output>200</output>

<result>200</result>