All young pioneers are divided into two groups: planting trees and digging holes, and the ratio of the number of people planting trees and digging holes is 3:4. If 2 people are transferred from the tree planting group to the hole digging group, then the ratio of the number of people in the tree planting group and the hole digging group is 2:3, please count how many Young Pioneers participated in this tree planting activity?
全体少先队员分成栽树和挖坑两组，且栽树和挖坑人数比是3：4，如果从栽树组调2个人到挖坑组，那么栽树组和挖坑组人数的比就是2：3，请你算一下有多少少先队队员参加了这次植树活动？
<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/7) - (2/5)</gadget>
<output>1/35 = around 0.028571</output>

<gadget id="calculator">2 / (1/35)</gadget>
<output>70</output>

<result>70</result>