Four classes in the sixth grade participated in the tree planting activity. The number of trees planted in the first class accounted for 20% of the total, and the number of trees planted in the second class accounted for 1/4 of the total. The ratio of the number of trees planted between the third class and the fourth class was 5: 6. It is known that the first class planted 12 fewer trees than the second class, how many trees were planted by the third class?
六年级四个班同学参加植树活动，一班植树的棵数占总数的20%，二班植树的棵数占总数的(1/4)，三班与四班植树棵数之比是5：6，已知一班比二班少植树12棵，三班植树多少棵？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/4) - (1/5)</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">12 / (1/20)</gadget>
<output>240</output>

<gadget id="calculator">1 - (1/5) - (1/4)</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">240 * (11/20)</gadget>
<output>132</output>

<gadget id="calculator">5 + 6</gadget>
<output>11</output>

<gadget id="calculator">5 / 11</gadget>
<output>5/11 = around 0.454545</output>

<gadget id="calculator">132 * (5/11)</gadget>
<output>60</output>

<result>60</result>