The ratio of the number of surviving trees to the number of dead trees in a batch of trees cut by Class 1 is 9:1. What is the survival rate of this batch of trees?
六1班裁的一批树，成活的棵数与死了的棵数比是9：1，这批树的成活率是多少
<gadget id="calculator">9 + 1</gadget>
<output>10</output>

<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

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

<gadget id="calculator">(9/10) * 1</gadget>
<output>9/10 = around 0.9</output>

<result>9/10 = around 0.9</result>