The greening team will plant 2,100 trees, 900 of which have already been planted, and the remaining 15 days will be completed. How many trees do you plant every day?
绿化小队要种2100棵树，已经种了900棵，剩下的15天完成．剩下每天种多少棵？
<gadget id="calculator">2_100 - 900</gadget>
<output>1_200</output>

<gadget id="calculator">1_200 / 15</gadget>
<output>80</output>

<result>80</result>