There is a tree with a height of 2.5 meters next to the flagpole of the school. At 10:00 in the morning, Xiao Ming measured that the shadow of the tree was 2 meters long, and the shadow of the flagpole was 6.4 meters long. Please use the knowledge of proportions to find the actual height of the flagpole.
学校旗杆旁边有一棵2.5米高的树，上午10时小明测得树的影子长2米，旗杆的影子长6.4米，请你用比例的知识求出旗杆的实际高度．
<gadget id="calculator">2 / 2.5</gadget>
<output>0.8</output>

<gadget id="calculator">6.4 / 0.8</gadget>
<output>8</output>

<result>8</result>