In March this year, students from the extracurricular activity group of Xiangyang Primary School voluntarily planted 200 trees, and 20 of them failed to survive. What is the survival rate of their tree planting?
今年三月份，向阳小学课外活动小组的同学们义务植树200棵，其中有20棵未成活，他们植树的成活率是多少．
<gadget id="calculator">200 - 20</gadget>
<output>180</output>

<gadget id="calculator">180 / 200</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>