The school will plant a batch of saplings on campus. If the survival rate of these saplings is 80%, how many saplings must be planted to ensure that 160 saplings will survive.
学校要在校园内栽一批树苗．如果这批树苗的成活率为80%，要保证成活160棵树苗，至少要栽多少棵．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">160 / (4/5)</gadget>
<output>200</output>

<result>200</result>