Class 2 students planted trees, boys planted 20 trees, 18 survived, girls planted 15 trees, and 10 survived. What is the survival rate of this class planting trees?
六2班学生植树，男生植树20棵，成活18棵，女生植树15棵，成活10棵．这个班植树的成活率是多少？
<gadget id="calculator">18 + 10</gadget>
<output>28</output>

<gadget id="calculator">20 + 15</gadget>
<output>35</output>

<gadget id="calculator">28 / 35</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(4/5) * 1</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>