Class 4 and Class 1 participate in tree planting and divide into several groups. If there are 10 people in a group, it will be just finished; if there are 12 people in a group, there will be a difference of 12 people. How many people participated in the tree planting?
四1班参加植树，分成若干组，如果10人一组，正好分完；如果12人一组，差12人．参加植树的有多少人？
<gadget id="calculator">12 - 10</gadget>
<output>2</output>

<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">6 * 10</gadget>
<output>60</output>

<result>60</result>