The students planted trees, and Xiaogang planted twice as many trees as Xiaohong, and three times as many as Xiaoqing. Xiaohong planted 12 trees, how many trees did Xiaoqing plant.
同学们植树造林，小刚栽的棵数是小红的2倍，是小青的3倍．小红栽了12棵，小青栽了多少棵．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">12 * (2/3)</gadget>
<output>8</output>

<result>8</result>