Four students planted trees, the first student planted half of the total number of trees planted by other students, the second student planted 1/3 of the total number of trees planted by other students, and the third student planted The tree is (1/4) of the total number of trees planted by other students, so the fourth student just planted 13 trees. How many trees did the four students plant in total?
四位同学去种树，第一位同学种的树是其他同学种树总数的一半，第二位同学种的树是其他同学种的树总数的(1/3)，第三位同学种的树是其他同学种的树的总数的(1/4)，则第四位同学刚好种了13棵，问四位同学共种树多少棵？
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

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

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

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

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/3) - (1/4) - (1/5)</gadget>
<output>13/60 = around 0.216667</output>

<gadget id="calculator">13 / (13/60)</gadget>
<output>60</output>

<result>60</result>