The students participated in the labor, and 28 people planted 84 saplings in one hour. At this rate, the number of people increased to 50, and the working hours were extended to 3 hours. How many saplings can be planted in total?
同学们参加劳动，28人1小时栽树苗84棵，照这样速度，人数增加到50人，工作时间延长到3小时，一共可以栽树苗多少棵？
<gadget id="calculator">84 / 28</gadget>
<output>3</output>

<gadget id="calculator">3 * 50 * 3</gadget>
<output>450</output>

<result>450</result>