There are 180 pine trees, which are more than poplar trees (4/5). How many poplar trees are there?
松树有180棵，比杨树棵数多(4/5)，问杨树有多少棵？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 + (4/5)</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">180 / (9/5)</gadget>
<output>100</output>

<result>100</result>