The poplar trees planted in the campus are pine trees (3/4), and the pine trees planted are willow trees (4/5). It is known that there are 120 poplar trees planted. How many willow trees are planted in the campus?
校园里栽的杨树是松树的(3/4)，栽的松树是柳树的(4/5)，已知栽了120棵杨树，校园里栽了多少棵柳树？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">120 / (3/4) / (4/5)</gadget>
<output>200</output>

<result>200</result>