bamboo pole is 2 meters long. Stand it upright on the ground and measure its shadow length of 2.5 meters. At the same time and at the same place, measure the shadow length of a big tree as 12 meters. What is the height of this big tree in meters?
一根竹竿长2米，把它直立在地面上，量出它的影长2.5米，在同一时间同一地点量得一棵大树的影长为12米，这棵大树高多少米．
<gadget id="calculator">2 / 2.5</gadget>
<output>0.8</output>

<gadget id="calculator">0.8 * 12</gadget>
<output>9.6</output>

<result>9.6</result>