Weimin Garment Factory needs to produce 810 sets of school uniforms, and 360 sets were produced in the first 4 days. According to this calculation, how many days will it take to complete all the tasks?
为民服装厂要生产810套校服，前4天生产了360套．照这样计算，完成全部任务一共要用多少天？
<gadget id="calculator">360 / 4</gadget>
<output>90</output>

<gadget id="calculator">810 / 90</gadget>
<output>9</output>

<result>9</result>