Students in a certain school plant trees, the survival rate is 95%, 30 of them died, how many trees were planted by the students?
某学校学生植树，成活率是95%，其中有30棵树死亡，求学生共植树多少棵？
<gadget id="calculator">95 / 100</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">1 - (19/20)</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">30 / (1/20)</gadget>
<output>600</output>

<result>600</result>