The third grade participated in the tree planting activity. The first class planted 105 trees, and the number of trees planted by the second class was twice that of the first class. How many more trees were planted by the second class than the first class?
三年级参加植树活动，一班植树105棵，二班植树的棵数是一班的2倍，二班比一班多植树多少棵？
<gadget id="calculator">105 * 2</gadget>
<output>210</output>

<gadget id="calculator">210 - 105</gadget>
<output>105</output>

<result>105</result>