A, B, and C plant a total of 120 trees. A plants B and C's (1/2), and B plants A and C's (1/3). How many trees does C plant?
甲、乙、丙三人共植树120棵，甲植的是乙丙的(1/2)，乙植的是甲丙的(1/3)，丙植多少棵数？
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/3) - (1/4)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">120 * (5/12)</gadget>
<output>50</output>

<result>50</result>