There are 90 sweet-scented osmanthus trees on campus, and camphor trees are less than osmanthus trees (2/3). How many camphor trees are there?
校园里有桂花树90棵，香樟树比桂花树少(2/3)，香樟树有多少棵？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">90 * (1/3)</gadget>
<output>30</output>

<result>30</result>