School tree planting activities. Class 6 planted 25 trees, class 2 planted 30 trees, and the sum of the two classes accounted for 10% of the total number of trees planted. How many trees are planted in the school?
学校开展植树活动．六1班植树25棵，六2班植树30棵，这两个班植树的和占植树总数的10%．学校一共植树多少棵？
<gadget id="calculator">25 + 30</gadget>
<output>55</output>

<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">55 / (1/10)</gadget>
<output>550</output>

<result>550</result>